Never Change a Winning Team?

We investigate the question of how team membership change affects team performance. Results from a quasi-experiment of 129 four-member teams show that membership change hinders the performance of winning teams. We define a winning team as one that has achieved disproportionately high performance beyond what ordinary teams have not. In contrast to winning teams, we show that ordinary teams benefit from membership change. Furthermore, a longitudinal study of 666 video game sequels indicates that departing members cause detrimental effects on winning teams, whereas newcomers are the reason for the increase in ordinary teams’ subsequent performance. Through demonstrating that ordinary and winning teams are affected differently by membership change, we reconcile the conflicting findings in team membership change research and unearth the distinct effects of newcomers and leavers. We also propose winning teams as a vital new research avenue.