MEME REFERENCE

Metronome

Use when someone or something repeatedly swings between two opposite moods, opinions, states, or choices.

What it expresses: Rapid alternation prevents a stable position from lasting.
Example: Your group chat changes from 'cancel the trip' to 'book it now' every hour, so you label each side of the metronome.
When not to use it: A person makes one considered change and then stays consistent; a single transition is not oscillation.