The turn signal - a short history

I don't understand how people get their licenses if they can't learn to use a simple gadget, convenient located RIGHT BESIDE THE STEERING WHEEL.

 You don't even have to move your hand!! It can be reached with just a finger!!

 In 1938, turn signals were introduced to the standard makeup of the automobile. This fancy gadget was hooked up to lights at the front and the back of the automobile. To flick the switch was to let the drivers in one's immediate vicinity know that they planned on a) changing lanes either to their left or right or, b) make a left or right hand turn onto a perpendicular street.

 WHY is it so hard for people to use this invention that has been standard on cars for the last 73 years!?

I mean - do you realize you are not the only driver on the road?  Or are you convinced that the world can read your mind and we all know what your intentions at each intersection are?

Let me give you a piece of advice - I can't read your freaking mind, so use your freaking turn signal if you don't want me cutting you off!

That is what annoys me today.