Tim, there's not many targets/3d/stumps etc that I dont' hit. I feel very comfortable on rabbits out to 30 yards or so. I think I missed one deer out of the last 12 or so and that was with a deflection.
That said, we all miss and make bad shots. If you haven't, you simply haven't hunted enough. Last year I missed a 100# hog at 15 yards not once, but twice...then the 3rd shot deflected! I felt stupid, was angry with myself and my boneheaded performance. Again last year, I was rushing to do a follow up shot on an animal that already had a buddies arrow in it and missed right under it clean as a whistle. Luckily, another fine archer was there and finished it off later on. It happens. But it can also be worse: This year, I hit a bear too high and lost it after a very sparse blood trail. I felt a whole lot worse....I think I'd take the miss for sure over a bad hit.
Shooting at targets is a whole different game than shooting at live critters, at least in my opinion. The only way to really get proficient at shooting live game is to take shots at live game. I find if/when I miss, I have neglected to pick THE spot (as bro Ray Hammond would say). 3d and stumpin helps, but it sure doesn't gaurantee a good shot on game. Keep at the practice and then pick THE spot...eventually, you will settle into a good groove. Remember, pick THE spot!