The first time I saw FizzBuzz, I immediately assumed it was some sort of "trap" or "trick" interview question - that there's some deviously subtle little thing in it that you'll miss at first or second glance, as a "gotcha." It literally never occurred to me that it was, in fact, a basic "Can you code your way out of a paper bag given a map?" sort of question to check for basic code competence in languages.

Then I started interviewing, and... yeah. I get it now. It really is that simple, should take a competent coder a few minutes, and 80% of people interviewing will take 45 minutes to muddle their way through it.