Imagine that you are in conversation with someone. You are enthusiastically telling them a story when all of a sudden, they put their hand up and say "Stop! Don't speak."
How rude is that?
Well, that is exactly what it is like waiting at traffic lights. I turned out of my road, accelerate change into second gear, and I was about to turn right when - stop, the lights change to red.
Of course I do and I wait, but how rude!