What's the most underrated statistic in basketball?

Field goal percentage which is related to points per possession. So much emphasis is placed on a player's scoring that people overlook how many shots he's jacking up to score that much. If his percentage is low, he may actually be HURTING his team by scoring that much. Which is why field goal percentage is so important. I think guys like Allen Iverson wouldn't be so highly touted if they placed more emphasis on how many bad shots he takes to average 30 ppg. Sure he scores alot but the number of bad shots he takes to get there often ends up hurting his team.