What we lose when receipt of the benefit and fulfillment of the commitment are separated in time is the coupling of the motivations into, in essence, a single motivation. It would be strange in the future moment to say that we violate our earlier motivation when we no longer wish to fulfill our commitment. This is the central problem of bald commitments into the future: we cannot tie our future and present motivations together to yield a single “net” motivation for action.

Russell Hardin, Trust and Trustworthiness, loc. 205