Holy cow, I wrote a book!
My favorite bad CD-ROM drive from Windows 95 was one where the
manufacturer cut a corner to save probably twenty-five cents.
The specification for CD-ROM controllers indicates that each can host up
to four CD-ROM drives. When you talk to the card, you specify
which drive you wish to communicate with.
The manufacturer of a certain brand of controller card
decided that listening for the
"Which drive?" was too much work, so they ignore the drive
select and always return the status of drive 1.
So when Windows 95 Plug and Play goes off to detect your
it finds four of them.
Apparently this was a popular card because the question came up
about once a week.