On somewhat of a side note, I think asshole is probably the most degrading insult ever. Hear me out:

An asshole is literally a hole, and a hole is a hole because it is empty, so you are calling them empty. However an ASShole is sometimes filled with shit, which is disgusting, but either way, the shit isn’t in the hole for long. In that sense, you are saying that this person exists as an empty hole which is sometimes filled with shit, but even the shit doesn’t want to hang around for long.