This is one of my own personal pet hates. To refrain from colourful language when I have the smalls in the car I tell them that the daft person in that car obviously bought the car that the turn lights came as an optional extra Grrrrrr!
Another one is people who park their cars on the pavement (sidewalk) – half on the road half on the pavement. But leaving no room for you to squeeze yourself past and definately not if you have a pram. When I get old I think I’ll be one of those old ladies that has an empty pram to push around and then I can ram them down the side of these cars. The nice young policeman won’t prosecute such a sweet old lady would they? :D

is the people who put it on while they are turning or just as they are switching lanes. The signal should be turned on before you turn or before you switch lanes as a warning so we all know what you plan on doing. If you turn it on just as you are changing, it helps no one! Grr.