The person who can hear no without punishing you is safer to make promises with.

How someone receives a refusal tells you what your agreements with them will cost. If a no brings coldness, a long silence, or a story about how you let them down, then every yes afterwards is partly bought under pressure. Promises made in that weather are not really chosen. Someone who can take a refusal without making you pay for it leaves your yes meaning something.

Notice what happens in the day after you decline something small. Watch the tone rather than the words. Where people take it plainly, you can commit more freely, and where they do not, keep your commitments smaller.