Turning down a good thing to leave room for a great one is terrifying. It’s also how most great things happen.

Every yes consumes capacity that is then unavailable to anything else. Good options are dangerous precisely because they are good, since there is no obvious reason to refuse and they fill the space quietly until nothing better fits. Declining something fine, with no guarantee of what replaces it, is genuinely frightening and often correct.

Look at your commitments and find the one that is merely fine. Ask what you would do with those hours if they were free. You need not drop it today, but knowing which one you would drop makes the decision fast when something better appears.