I had a wire nut come loose once. It was in a box at the peak of the garage where the floodlight is mounted. At first I thought the bulb had blown, but after all the hassle entailed in changing it, I discovered, no, there was no problem with the bulb. So I got to climb up the ladder again and remove the light fixture from the box. It was not that high up, but when I haven't been up a ladder for a while, it is extremely nerve racking. I fell once and I don't want to do it again. Anyway, pulled the light fixture, pulled the Romex back inside the attic, hooked up the light and it worked fine. I could only conclude that the wire nut had worked loose, probably assisted by alternating extremes in temperature (such extremes we have here in Hillsboro).
When I worked at Del Monte in Oakland (thirty years ago, for one tomato season), the electrician there always used screws and nuts to connect wires to motors, and then wrapped the connections with layers of electrical tape. The motors operated in a very wet environment so he was constantly having to change out motors, bring them into his shop and dry them in the oven.
4 hours ago