Vacillate

Etymology

From Latin vacillare, "to sway, totter, waver" — the unsteady movement of something that cannot hold still. The physical wobble came first; English applied it to the mind, so that a vacillating person sways between positions the way a loose post sways in the wind.

verb · /VAS-ih-layt/
To waver between choices or opinions, unable to settle on one.
What it names
The word for indecision in motion — swinging back and forth between options long past the point where a decision was due.
Example
He vacillated for weeks over the job offer, accepting it in his head each morning and declining it again by night.
Related idea
Oscillate is the neutral, often mechanical swing between two states; vacillate adds the human failing of not being able to choose.