Acting on one's immediate environment and doing tasks that need to be done cultivates brain circuits related to action and reward, which can lead to larger rewards.

“what you're saying is in the act of looking at one's immediate environment, acting on that immediate environment, we cultivate a relationship to these circuits in our brain about action and reward, that, at least to my mind, span the range of small things being rewarding, and then lead us to the bigger things being rewarding.”