[switch007]

To alert other people about your presence.

What would you do if a car was reversing and it looked highly probably they are going to hit you? Or when driving round blind bends on single track roads?

It has very valid use cases, it just happens to be abused by idiots quite often

[jxramos]

I think it's actually illegal not to have an operational horn. Sound travels faster than cars so it's a great mechanism to communicate presence during an emergency.

[andai]

Ah.. so the real question is, why do they still make idiots?