Believe it...
When I first started working in IT I had a job at a computer store where we assembled machines to order. The most common support call on new machines went like this:
Me: Technical Support, how can I help you today?
Customer: The computer I just bought from you won't come on
Me: (Standard reply that we worked out after the first 20 or so calls like this) Okay, on the right side of the computer, back near the big red on/off switch, next to where the power cable plugs in there is a fan, can you feel any air moving from it?
Customer: Uh, its working now (or Damn, you mean I have to plug this thing in?)
Me: No problem, thanks for calling.....
99% of the "It won't come on" calls were because the customer hadn't plugged the computer in.
The common one on the first laptops was "it ran for about 2 hours then just died and hasn't come on again. We normally charged up laptops before the customer picked them up. A suprising number thought it just ran off batteries and that you never had to plug it in an outlet....guess they just magically recharge themselves.....
This kind of crap is exactly why most of the Systems Admins I work with say that if we could just get rid of the users our lives would be so much simpler....lol