I was working for a home/small business computer service company who also sold custom-built PCs. We were more expensive than the big-box stores, but prided ourselved on personal, attentive service.
A few hours after selling an average system to one of our customers, we recieved a phone call:
Customer: "Hello, I just bought this computer from you guys, but it's put together wrong."
Me (alarms going off in head): "I'm sorry you are having problems, I've never heard of this particular complaint before, can you describe the problem in more detail?"
Customer: "Sure, the CD-ROM is installed upside-down."
At this point I was pretty sure I had a live one. But being the service company we are, I decided to give her the benefit of the doubt, she was after all, a very pleasant person to deal with.
Me: "Well, that certainly seems like a problem, I didn't think that was possible. I hate to inconvieniance you, but if you could bring the machine back down to our location, we'll take a look while you wait, covered under waranty, of course."
Customer: "Sure thing."
About 15 minutes later the customer walked in with her machine. We set up the machine on our bench and powered it up to test the CD-ROM (which on visual inspection, was installed correctly). About 20 seconds later, in a small, embarrased voice we heard from behind us,
Customer "Oh, it goes that way?"
The customer had installed her machine upside-down. the kicker is, out cases at that time had rounded tops, so she would have had to prop it up on both sides.