Consider a study I helped conduct, led by my doctoral student Aneesh Rai, which involved thousands of volunteers at a large nonprofit who had promised to work two hundred hours within a year of joining but were falling short of their pledge. Knowing that facing such a massive goal can be demotivating, my collaborators and I instead asked the volunteers to comm it to four hours each week or eight hours every two weeks-which, of course, is basically the same as two hundred hours a year. But these smaller commitments, despite amounting to the same annual pledge, yielded 8 percent more time volunteering overall than simply prompting people to make progress on a yearly commitment. (Likewise, the online financial services company Acorns has found that it’s more effective when people are asked to set aside monthly even though these amount to the same thing.) If a commitment is bite-size, it appears less daunting to us, and we’re more likely to stick to our world.