It's about how the FS does this stuff. Take for instance the old FAT filesystem from MS-DOS. If you use it on an SD/SSD (or even a USB key, that's more or less

It's about how the FS does this stuff. Take for instance the old FAT filesystem from MS-DOS. If you use it on an SD/SSD (or even a USB key, that's more or less the same tech), you're likely to burn it fast, unless the device does "wear-leveling" internally. Journaling filesystems like Ext4 avoid that by make it so that they don't overwrite again and again the same sector even if the system overwrites the same file again and again. Another aspect is resilience to system crashes or power outages. A sudden power outage can leave data half-written, including the file allocation table, which may result in severe data corruption. This is especially important for embedded devices, but not only. Some file systems are designed with that possibility in mind. Then there are performance considerations. FAT had to group sectors into clusters because of the limited number of FAT entries, so a little 1Kb file would actually use something like 8Kb on the disk (Windows still display both sizes BTW). There's also caching policies. If you want something "crash-proof", you don't want any write cache. But if you want something fast, you want a big cache. some filesystems pick resilience, others pick performance, others let you set the parameters you want.