A careful person notices variation before variation becomes failure.

Things rarely break without warning. They drift first, a slightly louder noise, a step that takes longer than it used to, a tone in someone’s messages that has changed a little. Failure is usually the end of a trend that was visible for some time to anyone who knew what normal looked like well enough to notice it changing.

Get familiar with the normal state of the things you depend on, whether that is a machine, a process, or a relationship. Then treat small deviations as information rather than as nothing. Asking about a minor change early is cheap, and it is the entire skill.