I missed a buck low this past season due to my string catching on a buckle. I probably took 40 shots at squirrels this year, and only killed 12. I will say that if they had been 3 inches taller, I'd have shot 30 or more. I gave a bunch some new hairdos. I don't know if they were ducking, or if I was just missing high.
I did miss a few shots at coyotes. I'm not complaining, though. All but one of my arrows went exactly where I was looking. The shots were a little long, and they had more than enough time to get out of the way. One, was trotting at around 27 yards. He made a Barry Sanders move, and the arrow missed right in front of him.
Another was about 30 yards. He literally sprawled on the ground and the arrow went right over him.
The last miss, I skewered the limb of a blow down I was trying to shoot through.