I know it's a rub to hear that it happens even you may very well be a responsible bow hunter and experienced enough to take down the deer or at least track it to its final laying spot. What I and FFD stated is the ones that seem to do go off to die and never retrieved by the hunter.
I have heard the words of justification "Well the coyotes will clean it up" My thinking is I don't want the packs roaming through my property taking the fallen deer targets, intended to be dropped when shot.
The cross bows get stronger the FPS get higher, the arrows get revamped to fly more accurate but they fail to drop the target it seems, as they slice right through them missing vital organs and the deer go off to die long distance away.
I have helped the neighbour in tracking the deer after the fact, blood stops a short distance from the hit, under growth or hay fields seem to mask everything so it's lost-till the cries of the pack-or the vultures circling.
Just saying that there should be a better arrow made that has the stopping power like a bullet can, can it be achieved I don't know. But I can say this, if there was, this hunt camp owner would have bought it and used it and everyone that went there to hunt would have had a gift of the better widget.
Many times I heard " I hate bow hunting" when they lost the deer.