Bad maintenance practices tend to sneak into the way things get done. This article includes three more to guard against.
Bad Practice #14 — Not testing breakers. While the adage "If it ain't broke, don't fix it" is generally good to follow, it does not apply to circuit breakers. The main reason is you can't know a breaker's condition without testing. It might actually be "broke" and in need of fixing (or replacement).
Bad Practice #15 — Not exercising breakers. The fact that a breaker hasn't tripped in several years doesn't mean the breaker is fine. It actually is an indication of the opposite. A circuit breaker is an electromechanical device with moving parts. If you never move the parts, it's very likely they won't move during that one critical moment when you need them to.
Bad Practice #16 — Not timing breaker trip. This is really part of testing (#14), but a part that sometimes does not get done. Over time, the lubricant degrades or disappears entirely, and that alone can impede breaker movement such that its tripping time is out of spec.