Sadly, the left side of this picture is a sign put up on an electrical box at my work.

The REALLY sad thing about this is that the hand written sign was taped
there by one of the electrical contractors that had been doing work there.

If someone can't spell "caution"... I would worry about their ability to wire
high voltage electricity.

The proper lock out tag on the right is what our engineers have in their office and
what THEY engineers use when a piece of electrical equipment is down for repair.