Saying yes to everything means you’ve quietly said no to doing any of it well.

Capacity does not expand to match your agreements, so every extra yes quietly reduces the attention left for the rest. The choice was always happening, just invisibly, and what suffers tends to be whatever has no deadline attached, which is usually the work you cared about most. Nobody sets out to spread themselves thin. It arrives one reasonable request at a time.

List everything you are currently committed to, including the informal ones. Then pick the two that matter and decide honestly what the others get. Telling somebody now is far kinder than disappointing them later.