zip drives are very well known for poor quality, and that is the case of why they die.
the quality is so bad, that after all these years i tried to open gently one and the hole you are supposed to push to release a tab just broke all the pastic, and i didnt even push it hard.
Once you open you see the mechanical parts...everything made of cheap plastic that bends easly. and there is not even 1 screw holding everything together, just holes on the case and in the hole goes another pastic leg, these guys went way cheap, i am surprised that not all died.
the power button for exampple is tied to the front cover with 2 dots of melted plastic
i even have one that doesnt even work , when i plug it in without any disc , both lights stay lit forever and does nothing.
that i saw with the first models zip100
not sure if the internal NEC ones are better, i think they should.