The promise you remember without a reminder is one less burden someone else has to carry.

A commitment you forget transfers a small administrative weight to the other person. They have to decide whether to chase you, work out how to phrase it, and hold the item open in their head in the meantime. None of that is visible from your side, which is why people who need reminding often believe they are reliable. Reliability is measured at the other end of the arrangement.

Write things down the moment you agree to them rather than trusting the feeling of having registered it. Keep the list somewhere you actually look. Delivering something before anyone has to ask is a quiet form of respect.