A couple had just moved in a house and called me to replace the ceiling fan in the living room. I pulled the flush mount cover down to start unhooking the wire nuts and noticed RG58 (coax cable). Someone had used the center conductor as the hot wire! I ended up running 12/2 Romex from the switch. There was no way in hell I could have hooked it back up the way it was. This is just one example I've come across.

I am not an electrician, but when I did projects, I did a lot of research before deciding to hire someone and then I was extremely confused when everyone was proposing doing it slightly differently.

A lot of them proposed ways that seem to violate the code, like running flex tubing beyond the allowed length or amount of turns.

Another example would be people not accounting for needing fireproof covers if they’re installing recessed, lighting in between dwelling in certain cities…

Heck, most people don’t actually even get the permit. They just do the unpermitted work.