Bootleg grounds…
The ceiling fan in our kitchen was falling apart so we opted to replace it. Unfortunately, upon pulling the old one down, we found a bootleg ground inside the wiring box where the previous owners intentionally attached the neutral wire to the ground wire since no real ground was available.
Wonderful. So we temporarily installed the new ceiling fan by grounding it to the wiring box. That way, once we upgrade the wiring, it will ground itself properly with no additional work. And there was much rejoicing…