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Ask HN: Why are 5 inch USB floppy drives so uncommon?

• RegnisGnaw 6y ago
  Why do you think the "the difference in demand alone can't explain this gap"?
  • polm23 6y ago
    I imagine there's little demand for 3.5in drives but they're readily available. Maybe the difference in demand is more than I assume it to be.
    • codingdave 6y ago
      I suspect the difference in demand is huge. I still have stacks of 3.5" disks sitting around the house. I haven't had a 5.25" inch disk sitting around since the early 90s.
      • RegnisGnaw 6y ago
        I'm about the same here. I should really order a USB 3.5" drive to get the last data off them this year.
        • tracker1 6y ago
          I got one about a decade ago as a just in case... it's in my garage somewhere, still in the box.
          • eatingCake 6y ago
            Doesn't the magnetic data on the disks fade over that time scale?
            • tracker1 6y ago
              Dunno... I don't actually have any 3.5" media... but got one because back then, I was more inclined to help people with things.
    • dboreham 6y ago
      Perhaps the missing piece of information is that: nobody makes any of these drives any more. The 3.5 drives sold are either old stock or refurbished. Heck I bought my last one (to make bootable floppy images for some patent litigation project) probably 10 years ago and that one was a refurb.
      • kps 6y ago
        Or _not_ refurbished, according to what I recall reading on some vintage-computer discussion — the typical Amazon-grade USB floppy drives contain scrap pulls that may or may not still work.
  • benibela 6y ago
    In school I was thought: with lower demands, come lower prices
    • marcosdumay 6y ago
      Somebody failed to communicate you the big picture. Usually, prices are higher if the demand is consistently lower. But that's not a certainty. Anyway, production and consumption are in (near) equilibrium, and the price is the communication channel that brings that (near) equilibrium. That doesn't imply in any price level, it's only a communication channel, where both sides input their preferences and settle on some value. The actual value depends on what are both sides preferences.
    • andrewf 6y ago
      Lower demand would be a shift from D2 back to D1 on this chart: https://en.wikipedia.org/wiki/Supply_and_demand#/media/File:Supply-and-demand.svg https://en.wikipedia.org/wiki/Supply_and_demand#/media/File:... But if the demand curve shifts leftwards or downwards enough, it won't intersect with the supply curve at all. At that point, the model says commerce halts because there's no price that both sellers and buyers are willing to trade at.
    • dsr_ 6y ago
      You left out a part: For commodity goods, lowering the demand will lower the price towards the marginal cost of production. A commodity good is interchangeable: you don't care whether you buy a bushel of winter wheat from Farmer A or Farmer B. A commodity good is produced by many entities and desired by many entities. Some goods are not commodities but are substitutable: when AMD made pin-compatible 386 and 486 processors, you didn't care much about whether a 40MHz 386 came from Intel or AMD, which is why AMD's lower prices let them build their marketshare substantially. If a widget isn't being produced at all, just sitting in a warehouse, the price can easily be governed by: - the person who needs a hundred of them vs the warehouse that would like to no longer pay an inventory tax on the 110 in stock - the broker who knows where the last hundred widgets are stored, and has figured out customers who really need them in ones and tens - the warehouse that thinks it has all the remaining widgets in the world, and advertises them at a high price to see if anybody wants them
• Aeronwen 6y ago
  There's no money in it. They couldn't sell enough to justify the costs of designing and building them.
• achairapart 6y ago
  Wondering about the price for the 8" version.
  • the_only_law 6y ago
    I actually almost bought a device with an 8" floppy drive. The device was not powering and I'm not an EE, and there were no discs for it anyway. I had a brief interest in maybe making my own, and did a little bit of research, but couldn't find much. IIRC I found one device that supposedly could interface 8" drives to a modern PC, but it seemed pretty involved. I ended up not buying the device, and kinda regret it now.
• kleer001 6y ago
  5.25" floppies were on their way out in the mid 1980s, USB was born in the late 1990s and 3.5" disks were still around and in high use then. It's a generational thing. https://en.wikipedia.org/wiki/Floppy_disk#History https://en.wikipedia.org/wiki/Floppy_disk#History https://en.wikipedia.org/wiki/USB#History https://en.wikipedia.org/wiki/USB#History The same reason there aren't Apple, Amiga, or Android branded Morse code keys.
  • polm23 6y ago
    I guess that makes sense, but the cheap USB drives you find on Amazon are of recent manufacture, so for some reason it makes sense to keep making them.
    • seiferteric 6y ago
      Lots of legacy systems, industrial machines etc. still use 3.5" floppies, so many people will still have a need to write them with modern computers to transfer stuff to these machines. My mom actually has a fancy sewing machine that uses 3.5" floppies for patterns and she uses a usb floppy drive to write to it.
    • foobarian 6y ago
      How else do you expect me to download pictures from my Sony Mavica /s
      • kleer001 6y ago
        Oh, man, I remember when that was state of the art and everyone in the computer art department would sign up weeks ahead to get a day's use of it and fill that disk with like 12 images. When was this? 1997.
    • magicalhippo 6y ago
      It might have changed by now, but at least a few years ago 3.5" floppies were still used to exchange crucial information in the health sector here in Norway.
  • 6y ago
• h2odragon 6y ago
  I dont have a working 5.25" or 8" floppy drive anymore; I wouldn't trust the 3.5" i have. imo floppy drives found in the field today, if working at all, are likely to only speak to themselves and not share media with another drive due to age and alignment issues. maybe one could detune a new drive to match an older ones quirks if necessary. I think the better approach is to treat reading the media as a one time recovery and then emulate the drive electrically; if you're working with an actual 5" disk somewhere. IIRC there's arduino boards that pretend to be a floppy drive and serve sd card images.
• alanfranz 6y ago
  I don’t see 5.25” disks since C64. All the PCs I have seen since 1990 had 3.5” drives, and that was the PC boom time. I doubt that there are a lot of 5.25 disks around, as many would have been converted already to 3.5”. On the contrary, I (40yo) own some 3.5 floppies (a couple of old big box pc games).
• s_gourichon 6y ago
  Not what you're asking for, but hey, this device http://www.deviceside.com/fc5025.html http://www.deviceside.com/fc5025.html is different from the standard USB floppy adapters. Standard is named UFI, spec at https://www.usb.org/sites/default/files/usbmass-ufi10.pdf https://www.usb.org/sites/default/files/usbmass-ufi10.pdf UFI does not provide actual low-level access to the drive. It only support a few common floppy formats, like 720kB, 1440kB and therefore not 1.2MB or 360k of the 5.25 inch floppies.
  • TD-Linux 6y ago
    UFI does actually support 1.2MB! This is because many Japanese computers, like the PC-98, spun their 3.5 inch floppies at 360rpm to match the sector layouts of the 5.25 inch one. Many USB floppy drives support this - if you insert a 3.5 inch disk and format it as 1.2MB you'll hear the pitch of the drive motor change.
    • s_gourichon 6y ago
      It's kind of tricky. UFI does mention 1.25MB, but the table states again "3.5 inch". So, yes, if you want to format your 1.44MB capable 3.5 inch disks as 1.25MB you can. But still not the 5.25 inch disks the OP is requesting.
• brk 6y ago
  The 3.5" drives had no practical disadvantages as compared to 5.25" drives, so the 5.25" units really declined in popularity and were EOL'd in most cases long before 3.5" drives disappeared. IIRC the interfaces and pinouts were different too. I would imagine that for many people, they moved any valuable data on 5.25" disks to 3.5" disks during the roughly decade of overlap of the two drive types. I doubt there is enough of a market demand for legacy 5.25" disks where the data doesn't already exist on other mediums to make it worthwhile to offer any kind of modern interface.
  • mywacaday 6y ago
    Bookmarking this as I am in a kick off for a project that needs to archive data in a regulated industry and the scope includes 5.25" drives. There always somebody!
    • robotnikman 6y ago
      Considering that people are archiving from other types of old media such as video game cartridges, its not too farfetched of an idea. There is probably a lot of valuable data still residing on some old 5.25 floppies
      • deleted 6y ago
        [deleted]
  • Zardoz84 6y ago
    Pinouts ? You know that you can connect a 5" and 35." drive on the same floppy drive port ?
    • tyingq 6y ago
      There were many 5.25" drives with edge card connectors. Hence this popular style of floppy cable that could connect different mixes of 3.5" and 5.25" drives. http://www.nullmodem.com/images/fddcable02.jpg http://www.nullmodem.com/images/fddcable02.jpg The power cables were typically a different connector as well.
• arthurcolle 6y ago
  in a similar vein, I love those mini CDs but they seem to have completely disappeared from the face of the earth. It's a shame, they were super cute.
  • interestica 6y ago
    I think with a lot of 'slot style' disk drives, those were incompatible. Made them a lot less practical.
    • myself248 6y ago
      I concur, especially given that automotive CD players are almost universally slot-loading. (And the rest are caddy-loading changers, which also only work with 120mm full-size discs.) That's the only thing I've burned CDs for in the last decade or so, thus 80mm minis are right out.
• dboreham 6y ago
  I sense an assumption that both sizes are equally likely to be required and available. That's quite untrue. 5.25 floppies immediately vanished from the market when 3.5 became available. That was a long time ago. So you have the entire lifetime of 3.5 disks elapsing after the demise of 5.25. We're now roughly 20 years after the demise of the 3.5 disk so both demand for and availability of the older 5.25 is very low.
  • ufmace 6y ago
    I wonder why they vanished immediately. When 3.5" disks came out, didn't people have data on 5.25" disks they wanted to continue to access for a while? I would have thought they'd be kept around as second drives on newer computers of the time for at least a few years.
    • toast0 6y ago
      They didn't vanish completely immediately, but it was pretty fast. When 3.5" drives came out, people were mostly buying first computers. A new computer user wouldn't have any old data, and most likely could find software on 3.5" disks as easily as 5.25" (unless they were buying seriously old software). You could certainly buy computers with both, and you could add a 5.25" drive to most computers if you needed to, but 3.5" was so clearly better that few people would.
    • ansible 6y ago
      5.25in drives did not vanish immediately. The transition occurred over a period of years. What really got things going in PC compatible land was the PS/2 series of desktops from IBM, which couldn't even fit a 5.25in drive in the case. At around that time it was somewhat common to buy a new PC that had both 5.25in and 3.5in drives, and the common clone makers (Gateway, Packard Bell, et al) could fit either or both in their more-or-less standard PC/AT form factor cases. For a while you could buy software that was on either format, and in some cases, like for utility software (Norton, etc.) they would include both in the box. Back when you still bought software in boxes...
    • ohazi 6y ago
• ogre_codes 6y ago
  Likely because the number of 3.5" drives shipped was on the order of 100-1000 times greater than 5.25" drives. There are still obscure devices shipping which use 3.5" drives.
• stuaxo 6y ago
  I've been looking into this and it's straightforward-ish. The greaseweazle is a new fairly low cost disk controller, and you can couple that with a 5.25" enclosure for a CDROM/DVD. The cheapest way is to buy an old full size external CDROM/DVD drive, then scavenge the case.
• ackbar03 6y ago
  Id be ashamed if I was caught with a 5 inch floppy
  • madengr 6y ago
    Though not an 8 inch floppy.
• blihp 6y ago
  You vastly underestimate the production gap between those two drive types. There were likely at least a couple of orders of magnitude more 3.5" drives in use in their time than 5.25" drives were in theirs. I remember my last 5.25" drive costing ~2x more than a 3.5" drive in the mid-90's. Also, widespread 5.25" drive usage ended 10-15 years before 3.5" drives were superseded by flash. 3.5" was also the last widely used removable magnetic disc and used by virtually everyone for a time for backups, in all kinds of industrial devices etc the way microSD cards are today. Sure, there were Zip disks etc. but those were typically add-on devices and had a degree of compatibility issues vs 3.5" drives which were standard equipment for well over a decade whether you wanted them or not. So the majority of computer users from that era (as well as any still in service equipment) are most likely to still have, and possibly need replacements for, 3.5" drives since they most likely switched over long ago and have been a rapidly dwindling replacement market vs 5.25" which was pretty much dead by the early 90's.
  • deleted 6y ago
    [deleted]
  • fingerlocks 6y ago
    Wow. Zip Disk really takes me back. A highlight of my childhood was sneaking a pirated copy of Doom 2 on a zip disk and secret installing it on a school computer. That game was like four 3.5" disks otherwise, not easy to conceal.
    • smoyer 6y ago
      My ex-main server has ZIP, JAZ and DAT all on the front panel.
      • ineedasername 6y ago
        DAT! I'd pretty much forgotten them-- in my first post-college job I had to manage a backup system that used them, swapping them each night before I went home. It really hammered home the importance of backups when someone completely hosed a database and I had to restore things.
• andrewf 6y ago
  I'll speculate. Companies started making these things in the late 90s, when it made sense. In 2020, it might make sense to keep selling drives. But nobody would start making and selling these drives today. A few things happened around the turn of the century: USB came in, 3.5" floppies went away, and laptops started to replace desktops for more people. 3.5" was clearly not the future, but customers had lots of recent work and data on them, that they needed to access from their new computers. The likes of Apple and Sony sold 3.5" USB drives with their new laptops (for way more than $10!). At some later point, Apple and Sony's customers had moved on, but the ecosystem of parts vendors, remaining customers, sellers etc would've been enough for the cheap generic vendors to move in. What happened instead with 5.25"? I'd say: the market was smaller, because 10 years of growth hadn't happened yet. The market was much more fragmented, most computers/OSes couldn't read disks written on another vendor's system. There were fewer pieces of $$$$ equipment (synthesizers, industrial controllers) that embedded them. And finally, the 5.25" -> 3.5" transition was pre-USB and pre-laptop, so desktop users just bought desktops with two non-portable drives using the native disk interface.
• anigbrowl 6y ago
  In addition to all the other reasons, 5.25" floppy disks were genuinely 'floppy' and easily damaged by wear and tear, so there are far fewer of them around in sufficiently good condition to be worth trying to read.
  • datavirtue 6y ago
    I had far more 3.5" floppies fail than 5.25" The "protective" door often blew up or would come apart in the drive. The hard shell and protective door would lead to people throwing the discs everywhere. The 5.25" was meticulously stored in a sleeve and disc case, only being exposed when inserting into the drive. Every time I find a 5.25" it glistens like brand new. Good luck getting data off any of these after sitting for a decade. I had to refresh discs (rewrite all the data) after sitting for only a few years.
• datavirtue 6y ago
  I remember lusting over 3.5" drives. I had a 32mb hard drive before I had a 3.5" floppy.
• Symbiote 6y ago
  I have a BBC Model B and a BBC Master, both with 5¼" drives. They were used a lot in British schools, and hung around into the early 1990s -- schools had invested in software for them, but didn't have the budget to replace them. My dad had an IBM 286 clone, which is the oldest computer I can remember using (Captain Comic!). That had both 5¼" and 90mm¹ floppy drives, but we almost always used the latter. All these machines were very expensive at the time, and not very common for home use. Are there any popular old computers (Commodore, Amiga, Mac etc) that used a 5¼" drive? My impression is everything was on cassette, until 90mm drives became cheap enough for home use. (Even the BBC machines sold for home use usually used cassettes; the disk drive was a separate, expensive purchase -- double the cost of the computer itself!²) ¹ Yes, I'm that much of a metric purist. ² http://chrisacorns.computinghistory.org.uk/Computers/BBCBI3.html http://chrisacorns.computinghistory.org.uk/Computers/BBCBI3....
  • myself248 6y ago
    > Are there any popular old computers (Commodore, Amiga, Mac etc) that used a 5¼" drive? My impression is everything was on cassette, until 90mm drives became cheap enough for home use. Your impression is very much mistaken. The Commodore 64 and Apple // were both equipped with 5 1/4" drives quite frequently, as were the Atari 400/800, the Tandy CoCo, etc. The TI 99/4A was usually found with cartridges and tapes, but could be equipped with a peripheral expansion box including a 5 1/4" drive. Anecdotally as a kid growing up in the 80s, 5 1/4"s were everywhere and I didn't see my first 90mm disk until years later.
    • ansible 6y ago
      Yes, the 5.25in drives were phasing out by 1990, in part because of the IBM PS/2 series computers. It wasn't uncommon to buy software that had the option of either (or in some cases both) in the early 1990's. What was really rare were the 8in floppy drives. Those were mostly on more expensive business systems (Tandy Model 2 for example) and minicomputers. I don't think I ever got to use a system that had those.
  • moonbug 6y ago
    > 90mm Ah, technical correctness, the best sort of correctness.
• interestica 6y ago
  Where are you seeing $10 usb/floppy drives?
  • the_only_law 6y ago
    Amazon, give or take a few dollars.
• myself248 6y ago
  The amount of data on 5.25" disks which is also in standard PC formats means that a standard USB-mass-storage implementation would have limited use. There are plenty of archival-quality solutions which perform low-level flux imaging of the media, and these do operate over USB. Because the 5.25" media saw application in tons of non-PC applications, and this is the kind of controller you need to do useful work with them. More info here: https://archiveteam.org/index.php?title=Rescuing_Floppy_Disks https://archiveteam.org/index.php?title=Rescuing_Floppy_Disk...
• jdswain 6y ago
  It looks like 5 1/4” drives themselves are getting quite rare, not many on eBay, while there are lots of 3.5”. So even with a controller, getting a drive is not simple. I’d say the main reason, is that 3.5” drives are much more common, and they overlapped USB They are much more standard than 5 1/4” drives too.
• tenebrisalietum 6y ago
  3.5" disks were in use partially into the 2000s and didn't really disappear until rewriteable flash media became common, cheap, and well supported among operating systems--which is about the time when Windows XP more or less took over 9x as the most common consumer OS. 5" disks were well on their way to being rare in 1990. I'd wager no system after the Pentium came out (and probably earlier, like maybe '92 or so) had a built-in 5" drive unless carried over from an older system.
• moonbug 6y ago
  Might as well ask why there are no 8" ones.
• jedberg 6y ago
  Almost everyone who had 5.25" media already converted it to 3.5" in the 90s. My first computer was 5.25" only, but when I built my second computer I put in one of those fancy new 3.5" drives along with a super fancy dual 5.25" and 3.5" combo drive. One of the first things I did was back up all my 5.25" disks to 3.5" and also copy them to the fancy hard drive I had in the new computer. Going from having 2 5.25" drives to having a hard drive and and 3.5" drive was an explosion in storage space and it just didn't make sense to keep using the 5.25" disks, especially given their high failure rates. Everyone I knew at the time did the same thing. 3.5" was vastly superior in storage and reliability (as long as you knew how to fix the springs in the metal covers on the disks).
• jandrese 6y ago
  Part of the issue is that while USB and 3 1/2" floppies overlapped for some time, the 5 1/4" floppy was already long dead by the time USB was introduced. I wouldn't be surprised if the 3 1/2" USB floppy drives you buy today are basically the same design developed in the late 90s. They're so cheap because they've been made the same way for decades now. The 5 1/4 USB drive is bespoke hardware, which is why it is so expensive. I'd imagine it has a more software described interface so it can handle the galaxy of incompatible sectoring and formatting standards used by different companies back in the day. It used to be that if you formatted a floppy on one computer it was not likely to work on any other brand of computers. Having the formatting details be in software/firmware would make the drive far more useful for historians.
  • maebert 6y ago
    ^ this reply should be right on top because it really captures the point. 3 1/2-USB drives existed “historically” because both technologies coexisted at the same time, just like you’ll find PS2-USB adapters, but good luck finding a PS2 to USB-C adapter.
• cflat 6y ago
  5.25" floppy disks are more likely to suffer physical damage at this point in history than a 3.5" disk. This would also contribute to the supply-demand curve biasing to 3.5" (on top of the ubiquity argument) 3.5" have a more durable design - the hard plastic, the spring loaded shield and, most importantly, the center disk that rested on the enclosure housing that prevented the magnetic medium from sagging. When 5.25" disks are stored on end, they sag over time causing them to physically be unreadable. You have to store them flat. 3.5" are (mostly) resistant to this sag and therefore will be more likely to survive long term.
  • souprock 6y ago
    3.5" disks are less durable. The sliding door snags inside the drive. This destroys both the disk and the drive.
    • Doxin 6y ago
      I can see the slider getting snagged, but I don't see how that can destroy the drive. At least for the model drive I have the slider clears way before the floppy gets near the head. Worst I can see happening is the floppy getting jammed inside, but that should be easy enough to fix given a screwdriver.
  • jfengel 6y ago
    That's what I was wondering: if you came upon a cache of 5-1/4" floppies, what are the odds of them being readable? How well will the magnetic media hold over, say, three decades? (While I'm sure there are lots of reasons you might want a floppy drive, the case I have in mind is "Hey, here are our old financial records from the 80s" or "I wonder what's on this disk in grandma's attic".)
• erickhill 6y ago
  Depends on the system(s) you are talking about. For the Commodore 64/128, there are multiple modern solutions using both USB and even microSD that emulate 5.25" floppy drives. My personal favorite, while not cheap, is the Ultimate1541. Over the years, due to its FPGA base, it has grown from a 5" drive emulator to way, way more.
  • dmurray 6y ago
    I think he's looking for the opposite: use a 5.25" floppy on a modern computer, instead of convince a vintage computer that you've got a compatible floppy disk.
• SecurityMinded 6y ago
  At the risk of pointing the obvious, did you think about when USB became prevalent and made almost any peripheral external, there were no more 5.25" floppy drives getting built into the machines. It is just the economies of scale. People who needed 5'25 inch floppy drives, either had one somehow or they converted their old media already. If there are handful of people who still are using or dependent on these devices, well, sorry, but you will either have to develop one using an Arduino/RasPi combo one way or another, or seek it from an obscure hardware supplier.
• smoyer 6y ago
  I've got a few in my basement ... my email is in my profile and if you'd like one, send me your shipping address. As a note, I'm about to throw out a huge pile of legacy electronics (I believe I have over half a ton going to the recycling facility so if there's a broad interest in old hardware, I could put together a list for the community. I'm going to part out an old Sun E450 and use the chassis and power supplies for a 40 node Kubernetes cluster. There are 20 7200 RPM 18GB SCSI drives in there as well as four CPU/memory units.
  • scrollaway 6y ago
    Definitely don't throw this stuff out. Especially with lockdowns around the world there's lots of hobbyist hackers around that would love nothing more than their hands on this stuff. And if you have any truly exotic hardware give @foone a shout on twitter, he does amazing write-ups on all sorts of crazy shit :)
  • cbm-vic-20 6y ago
    You might want to post some of that stuff at he Vintage Computer Federation[1] message board. [1] http://www.vcfed.org/forum/forumdisplay.php?28-Vintage-Computer-Items-For-Sale-or-Trade http://www.vcfed.org/forum/forumdisplay.php?28-Vintage-Compu...
  • 43920 6y ago
    This is something I might be interested in... please do make a list!
• dr-detroit 6y ago
  Why are yellowing Tandys and monochrome (green) monitors out of style? Young people are scum.
• cesaref 6y ago
  Yeah, well try and find an 8 inch floppy drive and USB controller... ;)
• gushie 6y ago
  Also remember that popular home computers often went from say ZX Spectrums (Cassette) to Amiga/Atari ST (3.5 floppy) - so there was no intermediate 5.25 floppy stage.
  • timthorn 6y ago
    It's pedantry and missing your point about progression to 3.5", but given this is wallowing in retro - you can't forget that the ZX Spectrum went to Microdrive and then, with the Spectrum+3, to the 3" (not 3.5") floppy :) https://www.sintech-shop.co.uk/zx-microdrive/a-3035/ https://www.sintech-shop.co.uk/zx-microdrive/a-3035/ https://www.dataserve-retro.co.uk/contents/en-uk/d56.html https://www.dataserve-retro.co.uk/contents/en-uk/d56.html
  • dade_ 6y ago
    Same here, Commodore V20 cassette & cartridge to Tandy 1000TL/2 3.5” single density.
  • octorian 6y ago
    That's gotta be a European thing. In the US, cassette drives were pretty much non-existent (in favor of 5.25" floppy drives) from at least the mid-80's onward, at least. I personally have absolutely no memory whatsoever of ever seeing anyone actually use a cassette drive to load programs on a computer. (though I did read about it in books on occasion). And I was a kid during the era of the Apple IIe's popularity, with machines of its ilk being my first exposure to computers. Even into the 386/486 era, at least before CD-ROM drives were commonplace, it was common for computers to have both 5.25" and 3.5" drives and to find software in either format.
• koolba 6y ago
  Surprised nobody mentioned iMacs. They were the first major desktop without a floppy drive but they did have USB. The first accessory for most was either a floppy or Zip drive.
• deleted 6y ago
  [deleted]
• ineedasername 6y ago
  3.5" drives came about as the home computing & internet movement was just starting to take off. Computers adopted the newer more compact technology just as there was an explosion in demand for computers. Their popularity then meant that legacy support needed to continue longer as well.
• FlyingAvatar 6y ago
  I would guess because 3.5” disks were prominent in PCs for much longer than 5.25” disks. When USB was introduced, it would be common for the PC to include a 3.5” disk drive but 5.25” had been out of favor for some time by then. On top of that it was common for drivers to be included on 3.5” that came with hardware, even for server grade hardware, this persisted for a long time. It was not uncommon even in the late 2000s for rack mount servers to include floppy drives for this reason. Lastly, because of their size 5.25” disks were rarely included in laptops and portables once 3.5” disks became available. Having 3.5” disks being prominent in laptops led to many miniaturized versions of the 3.5” mechanisms which translate well into a USB peripheral form factor.
• emrah 6y ago
  It's a shame, I really liked the "clong" sound the handle made when you locked the 5.25 floppy disk in the drive. IIRC 5.25 and 3.5 floppies had same amount of storage (in fact 3.5 a bit more). Combined with the fragility and size of 5.25 floppies (you couldn't just put it in your shirt pocket), they lost interest