1. Are they pass through shots through the lungs?
2. Does this person give the deer at least 30 minutes (given a good shot)? More time for a poor shot?
3. Is this person taking overly long shots?

Pass through lung shot deer always will drop (at least for me anyway). But if you push them, they could drop a long ways away and be tough to find with a poor trail left by a fast running deer. Even a good shot can go a few hundred yards, but if not pushed, you have a good trail.

I have had pass-through shots, from the ground level, that were just high of the lungs but below the spine and resulted in very little blood that quickly stopped. Never found the deer. Others have even said that they saw such shot deer weeks later on their cam. So I aim more dead center in the lungs.

Get this kid a shooting diagram so he can mentally prepare for a good shot.