I've had three zero mph falls and always with an audience of other riders. How embarrassing. My worst one was the first day I was riding clipless. After riding about 25 miles, crossing many side streets where we had to stop, clip out and clip back in, I was thinking I was on top of the world. 25 miles clipless without a single incident! Yay me! Then we pulled up beside a nice cool creek where there were about 10 riders stopped for a little rest and social time. We pulled up, I unclipped (I do the left side first). Leaned to the right with right foot still clipped in and skated right into the creek. Up to my knees in water up to my ankles in creek mud. It was humiliating.

Zero mph falls are what happens when you lose focus just a little. Gets ya every time.