Replaced a breaker that kept tripping and found the culprit in a loose neutral

Had a panel where the main breaker kept nuisance-tripping on a 60Hz hum I've been chasing for weeks — turned out a loose neutral on a shared circuit was feeding back through a dryer outlet. Tightened it, checked torque, and the hum just stopped. It's funny: we treat wires like they're dead metal, but the honest fix is the closest thing to peace I get these days.