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Sunk Cost Fallacy, if he goes through with it anyway?
If not for this anchor I'd be dancing between the stars. At least I can try to write better vampire stories than Twilight.
Neither really fit, it's a character whose goals change, and the realization that he's changed is sometimes an unpleasant one to him.
For example, at the beginning of Avatar Jake Sully doesn't particularly care for the planet or its inhabitants, faithfully obeying his superior's orders as a Marine in the hopes of getting his legs restored. By the time he learns that this can be arranged, Jake is already involved with The Chief's Daughter and spends more time as a Na'vi than his human body.
Many cases of Character Development involve motivation changes, anyway.
We can never truly eradicate the coronavirus, but we can suppress its threat like influenza
A character starts out with a very strong motivation. As he undergoes Character Development, this starts to change, until at some point the thing he originally wanted happens and he no longer wants it. As there was usually some difficulty in getting it to happen, there is much conflict created by Bob not wanting to be an Ungrateful Bastard.
For example, Bob is a member of an anarchist society who really wants to overthrow the corrupt system, and volunteers to perform a likely-suicidal mission a few months down the line. But in the meantime, he finds a girlfriend and a job he enjoys, meaning he's nowhere near motivated enough when the time comes for him to fulfill his promise.