You shouldn't purposely upset other drivers.
Carl is driving on the highway on his way to work on the other side of town.
Carl wants to get into another lane.
Carl slows down and waits until another drivers lets him merge into the lane.
Carl flips off another driver and honks his horn at him as he swerves into the lane.
The other driver waves at Carl and follows him at a safe distance until they get to the red light.
The other driver rams into the back of Carl's car and breaks the bumper.