Usage rate, a.k.a., usage percentage is an estimate of the percentage of team plays used by a player while he was on the floor.
By balancing usage rates and the varying offensive ratings of the five players on the court, a team can achieve optimal offensive output. The stats show that, for all players, as the player uses more possessions, his efficiency decreases. What defines a superstar, in Dean Oliver‘s statistical analysis, is that he can shoulder a larger proportion of a team’s possessions with only a relatively small drop in efficiency. Meanwhile, the opposite is also true: players perform more efficiently when they are asked to use fewer of their team’s possessions. As a result, the greater burden on the superstar means that supporting players maintain low usage rates, allowing them to operate closer to their peak efficiency.