My very first juvy hunt I sprayed more bullets than a Rambo movie. Hit nothing.
The most times I've had to shoot a deer would be four times. He went down on the first. I put another in him when I walked up on him. A few seconds later he was still breathing and trying to stand so I shot again. That one knocked him on his side and when he tried to pick his head up I put one between his shoulder blades. When I gutted him I found the first bullet hit high and far back (I blame myself. Probably flinched.), the next two destroyed his lungs and the final one shattered his spine between the shoulders.
I felt bad about it later for having to use that many shots, but after thinking it over he probably would have expired fairly quickly after the second shot. I was so nervous and jumpy I just kept trying to put him down. That was the second year hunting after killing my first and the first deer that didn't die within seconds and out of sight. In my hunters ed. class they talked frequently about taking this seriously because even though it's just an animal you're still taking a life and it should be done quickly. Seeing it up close like that was a big deal.