Winning a title is perhaps the hardest thing you can do in mixed martial arts, only rivaled in difficulty by defending it. Of the UFC’s 114 unique interim and undisputed champions, 52 (46%) never saw a successful defense of their belt. Although retaining a belt is hard work, breaking down defense statistics paints a better picture as to which weight classes are harder than others to stay at the top of.
Before we begin, it is worth noting the decision to omit interim champions from the conversation was almost had with how much they skewed the stats in one direction.