Put it this way, there are very few (maybe none) controversies involving the ref either stopping it too early or too late (Tito v Ken II springs to mind but even so I thought it was a good stoppage), where as there literally thousands of fights in boxing tarnished by an awful referee or decision, it happens very often, and not just little ones too, but main events, world title fights etc. Another yard stick is the fact that there has never been a death or serious injury in the history of the UFC.