[FabHK]

> constraints of an ipod (one per user)

Do you mean one user per iPod? (because you could obviously have many iPods per user... Apple certainly didn't object :)

But yes, you couldn't use iPods to merge iTunes libraries among friends. For that, you needed an external hard drive (and you could mount the original iPod as an external hard drive and copy the music over, but then those mp3s were seen as data, not music, and could not be played...). And once the iTunes music store got introduced, music you bought there was DRM'd, so that complicated things further.

But I don't think it was deliberately designed to "maximize hardware sales". You could easily wipe it and sync to another user in a few minutes (the original Firewire had 100 to 400 Mbit/s, so say 3 to 10 minutes to replace the entire 5 GB library, so quicker than charging it).

I'd venture that the constraints were demanded by the music industry, not imposed by Apple to maximise hardware sales (how is "needs iTunes" maximising hardware sales?).