Put a thumb on the scale once and you’ll never fully trust that scale again. Same with your word.

Trust is asymmetric. It takes a long time to build and one incident to turn into a question that never fully closes, because after a single tilt the other person has to wonder about every reading from then on. Nobody is deciding you are a liar forever. They have simply lost the ability to stop checking, and that checking is the real cost.

Keep your promises small enough to actually keep this week, and say no where you cannot. If you broke one recently, name it yourself before somebody else does. Then be boringly reliable for a stretch, because nothing else resets a scale.