- The Amiga 500 and 1200 were too expandable. The worst thing Commodore done was providing the A500 with a side connector that allowed pretty much anything available on their big box A2000 to be used on the A500.
Amiga 500 expansions (except 512 kB ram expansion) were rare and insanely expensive.
CDTV - Designed to be user friendly. This was hardly the case with terrible disc caddy system, old 1.3 ROMs and no in-built floppy drive (when all Amiga software to that date was released on floppy) made no sense
Commodore never invested to the OS development anyway. But then Commodore always was a hardware company that never understood the software.