I'm sure most everyone knows my take on this subject, and not nearly everyone agrees with it. None the less, here it is.
I don't care how good a shot one is, or how hard one tries, bad hits are going to happen. When things go badly, the bow one chooses to use makes absolutely no difference at all. The things that do matter are the skills and knowledge of the hunter himself (as gehrke145 states) and the arrow he or she chooses to hunt with.
I bowhunted for 24 years without keeping any kill records; but I do have them - in painstaking detail - for the last 26 years. Across those last 26 years, with traditional archery gear, I have a big-game wound-loss rate of 0.638%. Don't misread that. It is ZERO POINT 638 PERCENT; or an equivilent wound-loss rate of 6.38 animals per one-thousand HITS.
The actuality of the numbers is four hit and non-recovered big game animals against 623 hit and recovered big game animals; regardless of the reason for non-recovery. One of those four was purloined by other hunters, and three simply went where I could not follow (one into a deep water swamp and two into uncrossable mud flats). Nonetheless, and allowing no excuses whatsoever, those four animals I did hit and I did fail to personally recover. They were wounded by me and not recovered by me. They count as wounded and lost; and that is as it should be. No 'assuming' that a hit animal is going to fully recover from a hypothetical 'non-lethal' hit just because we didn't, or couldn't, locate it.
I'm absolutely convinced that the major reasons for the high wound/loss rate(s) consistently shown by the many studies of bowhunted game are: (1) the arrow setups most commonly used by bowhunters and (2) the skills and knowledge of the hunter(s) involved. Those two reasons are closely interrelated, and some might reverse the order of the two; and I certainly could not say they were wrong, Regardless of the order of reasons, neither are insurmountable obstacles.
For years I did terminal ballistic studies on rifle bullets. My traditional archery wound-loss rate is LOWER than that for the animals I've taken with firearms. It is also lower than that of any of my friends, acquaintances or hunting partners who use compound bows. That's not putting any of them down. That are all learning and getting better by the year. My own wound-loss rate wasn't all that great during the years I was learning "how to hunt".
It's up to each hunter to look after out sport. Bowhunting is essentially a one-on-one exercise; hunter verses the quarry. We each make many, many choices that directly affect our individual success rate; and we each must live with each and every one of those choices. It is each hunter's responsibility to educate himself and act accordingly. That's something that can never be cured by a law written on a piece of paper. WE EACH ALSO HAVE AN OBLIGATION TO PASS ALONG WHAT WE KNOW TO THOSE THAT FOLLOW IN OUR FOOTSTEPS; AND THAT TOO IS BEST DONE ON A ONE-TO-ONE BASIS.
It's all up to each of us. We must each do our own part. Hunting is, and always will be, personal; for however long the right to hunt survives ... and that depends on US!
Ed
TGMM Family of the Bow