Many adults today lack self control and this is because they were not taught the importance of self control from childhood. Many young adults have fallen into trouble they simply could have avoided if they had self control.
Teach Your Child the importance of having self restrain, he must not react to every situation. It is only cowards who can not hold back from fighting at school instead of reporting to school authority when taunted by their fellow student. Self control will help your child to stay calm when people taunt them and wants them to get into a fight.
Self control is for leaders and not followers, leaders are careful before they react or take an action because they have self control but followers simply react spontaneously damning the consequence of their action. Make your child a leader by teaching him self control early in life.
As an adult self control will help your child not to make some costly mistake or even cheat on his partner when tempted. Self control will help him withstand the pressure of a hostile boss and not get into a quarrel or argument with the boss.
It is your duty to start early enough to inculcate this value in your child,it will go a long way in helping him now and in the future.