Fine day today? Um no thanks

I was just wondering: - why do they call it a traffic fine?
I mean if you think about it, it's hardly 'fine'! It's actually very horrid! It means your handling of traffic was anything but 'fine'!
In fact pretty much where ever the word 'fine' is used as a noun implies that you're about to lose money and that you're not going to feel 'fine' for a while!!!
Just saying...