I spent a couple summers working for the sustaining engineering department of a manufacturing company. There was quite an oil boom and they were having trouble hiring enough people for the shop floor, so they had the engineering staff come down to help for a few days. The mechanical engineers would bolt things together, the electrical engineers would do the wiring, etc.

Afterwards, one of the supervisors showed me the difference between wiring done by an electrician and wiring done by an electrical engineer. He pulled on each wire of the relay panel. The wires done by the electricians didn't move, but most of the wires done by the electrical engineers popped right out.