In this paper, we examine the changes in motivation factors in crowdsourced policymaking. By drawing onlongitudinal data from a crowdsourced law reform, we show that people participated because they wanted toimprove the law, learn, and solve problems. When crowdsourcing reached a saturation point, the motivationfactors weakened and the crowd disengaged. Learning was the only factor that did not weaken. The participantslearned while interacting with others, and the more actively the participants commented, the more likelythey stayed engaged. Crowdsourced policymaking should thus be designed to support both epistemic andinteractive aspects. While the crowd's motives were rooted in self-interest, their knowledge perspectiveshowed common-good orientation, implying that rather than being dichotomous, motivation factors move ona continuum. The design of crowdsourced policymaking should support the dynamic nature of the processand the motivation factors driving it.