How come fathers and sons don't ever get along?

Fathers feel the responsibility and importentness for their sons and their son's life , actions, and results. they fell as though they need to insure their son's happiness and well-being-and sometimes,the sons don't like their fathers pushing,pressuring, and being so nosy towards them. They also will sometime be so much alike that they can't stand each-son's can also fell that their fathers "screwed them up"