I think b/c of the glove size its just easier to tell how hurt a fighter is and how many clean shots they are taking in MMA versus boxing so its easier to make a good stoppage versus a premature one. I put a big onus on a fighters corner to have his best interest in mind. If a guy is just taking a beating but still able to defend himself the ref isn't going to stop it. Its on the corner to do the right thing.