The divergent impact of reward magnitude on goal eagerness and effort investment

When attempting to motivate an individual, does increasing the magnitude of the reward always have a positive impact on one's effort investment? Through six experiments, we demonstrate that although individuals working for a large (vs. small) reward are more eager to commence the task (Studies 1-5) and more likely to persist when encountering an opportunity to terminate the pursuit (Study 2), the intensity of their effort investment in the goal remains relatively unchanged regardless of the magnitude of the reward (Studies 1-5). The insensitivity of effort investment to the magnitude of the reward disappears in the following contexts: when the participants are reminded of the reward size during the goal striving phase (Study 3), when individuals make a plan prior to commencing the task (Study 4), and when a partial reward is allocated to each goal-directed action (Study 5). This divergent impact appears because the psychological processes and information that govern pre-initiation goal eagerness may differ from those that control post-initiation effort investment.