Couple of things to remember. Internet Archive is in the world scale. And you are already using a proprietary format with that book from 10 years ago. The post

Couple of things to remember. Internet Archive is in the world scale. And you are already using a proprietary format with that book from 10 years ago. The post talks about keeping a tab on all the books available in Internet Archive. Which is a freaking huge number. Then keep them all up to date available in at least a single format is a problem. Not to mention some books would only be available in epub, some only in pdf and some are just txt files. And users would want books to be available in certain formats too. Keeping that number of books up to date from a librarian's POV (like internet archive) is really hard. The formats, the software etc. This is why they counter the marketing of publishers that says "digital copies are forever". They are not. There is server, hard disks, then the software of it all and a never ending dependency hell and issues like that. Just add security to the mix and then boom, it's already crazy hard. Another intersting thought would be, can you try to keep all the digital books you own Into a multiple formats? Everything! The free ones you downloaded like the pdfs, the epubs and all the formats including probably the technical books you own. Try doing that. Then during a sale, you buy books from humble bundle and some books are only in pdfs. Uff. Now you need to make all those pdfs into mobi format so that you can read them in your kindle. This effort for dealing with this and software needed for that should paint a good picture. Now scale it up to the whole world with multiple languages and bizillion editions and so many more complexities. :D PS: I am not arguing. Just thought you might have overlooked the context. If I misjudged, my apologies. :)