Competing Motivations: When More Incentives Lead To Less Effort

Abstract

I propose a framework of competing motivations that suggests a weak incentive can diminish the appeal of a strong incentive. This occurs when their motivations interfere with one another, rather than simply adding up. Consequently, combining a strong and weak incentive scheme can be less effective than offering the strong incentive alone. I demonstrate this in two pre-registered experiments on MTurk CloudResearch (N = 2,517). In the first study, participants completed effort tasks incentivized with monetary rewards, charitable rewards, or both. Those motivated solely by monetary rewards completed 23% more tasks than participants offered the same monetary reward paired with a charitable incentive. In the second study, participants completed tasks incentivized with monetary rewards, a chance to win a gift card, or both. Participants offered both incentives did not perform better than those offered only monetary rewards; when accounting for heterogeneity in preferences for the gift card incentive, the combined incentive scheme resulted in significantly fewer tasks completed compared to those working only for monetary rewards. These findings support the competing motivations hypothesis and underscore the need to reconsider the conventional additive approach to incentive design.