Not about "hitting the deer!"
Most people who have been hunting for a while know that it is not about hitting a deer, whether that is with a longbow, recurve, compound, crossbow, muzzleloader, or scoped rifle. It is about taking and making a shot that you are sure will kill an animal. Just hitting it is about the worst thing you can do, for the animal, and for the hunting community as well, with all the antis out there making noise as often as they can. Keep your shots to a range that you are sure you can kill, not just hit, and you will be much happier.
Also, learn to track until you exhaust every possibility that might find it. Unfortunately, I have been there, and it is a sickening feeling. If you wound a deer and it goes off to die without being recovered, I think that is the worst thing I can do while hunting. I'd rather not see anything at all than that. But, if it does happen that you wound one, track it until you have no more possible chances to pursue.
JMHO