About 25 years ago, when I was transitioning into industrial maintenance, an old army buddy and his wife were visiting over the Christmas holidays. We'd spent the evening drinking, went back home and everybody retired for the night. Just as I was turning the lights out, my pager went off in that annoying fashion that they have. Even though it wasn't my week to be on call, I answered the page anyway (new enough at the job to want to appear reasonably eager to please).
The tech paging me was in full-on panic mode: He had what he swore was an electrical problem at a paper mill, and the entire mill would shut down in about two hours if he didn't get the machine up and running. I told him I was three sheets to the wind and not about to go to work in that condition. He said I was the only one who had answered his cries for help, and he was practically in tears. So I agreed to look at the problem, but he would have to pick me up and drive me back, and under no circumstances would I speak to the customer or touch the equipment - I would just point and tell him what to do.
Got back to the mill with about 45 minutes left before the shit hit the fan. Several mill supervisors standing around asking dumb questions. We went to the machine in question and shut the door behind us. The original tech showed me the problem - the motor would bump a little, but give no more movement before tripping the overloads.
I took one look and told him that the motor was fine, but the brake was so far out of adjustment that it wouldn't release. Not an electrical problem at all. Two minutes later everything was running smoothly, and I was in the passenger seat of his truck snoozing while he wrapped up the paperwork and basked in the adulation of a grateful customer!