A promise is a direction taken, a self-limitation of choice. As Odo pointed out, if no direction is taken, if one goes nowhere, no change will occur. One’s freedom to choose and to change will be unused, exactly as if one were in jail, a jail of one’s own building, a maze in which no one way is better than any other.

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You don’t understand what time is,’ he said. ‘You say the past is gone. the future is not real, there is no change, no hope. You think Anarres is a future that cannot be reached, as your past cannot be changed. So there is nothing but the present, this Urras, the rich, real, stable present, the moment now. And you think that is something which can be possessed! You envy it a little. You think it’s something you would like to have. But it is not real, you know. It is not stable, not solid—nothing is. Things change, change. You cannot have anything. And least of all can you have the present, unless you accept with it the past and the future. Not only the past but also the future, not only the future but also the past! Because they are real: only their reality makes the present real. You will not achieve or even understand Urras unless you accept the reality, the enduring reality, of Anarres.

Ursula K. Le Guin, The Dispossessed: An Ambiguous Utopia

Came across this quote in this post.