How do different types of motivation influence the politics of collective action? We study a model of endogenous rebellion and repression to understand how different types of individual motivation affect participation, state repression, and the mechanisms by which state violence affects political contention. Unlike psychological rewards, material rewards are divided among successful rebels. Thus, in material rewards settings, repression that decreases mobilization and chances of success also increases participants’ share of the rewards, reducing repression’s effect. Consequently, materially rather than psychologically motivated groups are less affected by repression and face less repression, but they are also less able to turn early failures into future successes. Moreover, because repression is more effective and used more when rebels are psychologically motivated, rebel motivations are a confounder in estimates of the relationship between repression and mobilization. This can lead to overestimation of repression’s effect and to more statistically significant results exactly when repression is more effective.