What is something you used to believe, preferably something concrete with direct or implied predictions, that you now know was dead wrong. Was your belief rational given what you knew and could know back then, or was it irrational, and why?
Edit: I feel like some of these are getting a bit glib and political. Please try to explain what false assumptions or biases were underlying your beliefs - be introspective - this is LW after all.
The job market isn't just Google. Is it really true that anyone who can program FizzBuzz will immediately get snapped up by the first place they apply to, if they are not applying to someplace like Google which receives such large numbers of applications? I find it hard to believe that the average accounting company or bank that needs programmers has to do 100 interviews on the average every time it hires one person.
(Furthermore, multiply by how many competent programmers they go through. If they hire on the average 1 out of every 4 competent programmers who applies, that makes it 400 interviews for each new hire.)
You seem to be confusing applicants with people who are given interviews. Typically less than half of applicants even make it to the interview stage- sometimes much, much less than half.
There's also enough evidence out there to say that this level of applicants is common. Starbucks had over a hundred applicants for each position it offered recently; Proctor and Gamble had around 500. This guy also says it's common for programmers.