People struggle to stay motivated to work toward difficult goals. Sometimes the feeling of difficulty signals that the goal is important and worth pursuing; other times, it signals that the goal is impossible and should be abandoned. In this paper, we argue that how difficulty is experienced depends on how we perceive and experience the timing of difficult events. We synthesize research from across the social and behavioral sciences and propose a new integrated model to explain how components of time perception interact with interpretations of experienced difficulty to influence motivation and goal-directed behavior. Although these constructs have been studied separately in previous research, we suggest that these factors are inseparable and that an integrated model will help us to better understand motivation and predict behavior. We conclude with new empirical questions to guide future research and by discussing the implications of this research for both theory and intervention practice.