There are multiple possible interpretations:
For some reason your candidates have the neccessary ability. Possibly due to pre-selection, job profile, your area, whatever.
Your excel setup leads itself for easier realization of the FizzBuzz test.
Not having programming experience may actually help here as there is no standard solution where you can get stuck.
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.