I believe that anyone who as hunted for any amount of time has hit and not recovered a deer. For many reasons, and there are many variables. It is hard to evaluate this shot by just a photo. We do not know how long this particular arrow shaft is, nor do we know what kind of broad head, or the distance, or the shot opportunity. They are all factors and any one of them can result in a wounded animal. A sharp broad head is often overlooked. It is important because the broad head needs to cut through flesh, tissue, and organs to cause hemorrhaging for the animal to die quickly. Make sure your broad heads are sharpened or new. If this person took a hail Mary shot and his arrow lost enough inertia to penetrate the animal then it was a bad decision on behalf of the hunter. Maybe the shot was through brush and the smallest twig threw the arrow off course. Again a bad shot choice. But there are times when everything can be perfect and the 6th sense of the deer wins out over our skill. As Flatlander said, just a fraction of an inch either way can put this arrow into no mans land and the deer winds up surviving.
It makes everything we do that much more important. Please do not overlook or take lightly any aspect of hunting. The skills that we as hunters have constantly need to be honed so we can be the very best that we can be.
I have wounded many deer in the years I have hunted. It is terrible. I try to evaluate my circumstance and learn as much as I can from it so that I do not repeat the same mistake twice. (However...I am very good at making a whole new set of mistakes.)
Happy Hunting Y'all.