The Function of Punishment on the Students / Children

As teachers or even parents unfortunately we ever faced with sentencing on the students / child. For example if our students come late to school or if our students are not necessarily homework, we will give punishment to him. Extent of punishment was not related to physical and mental effects that result in severe punishment I think the students / children can be justified.

The purpose of punishment on their students / children:
a. Restricting children to undesirable behavior is not repeated.
b. Educate in order to become accustomed.
c. Motivate, to avoid the occurrence of social behavior that is undesirable.

But if the punishment was the last action that can be done to motivate, educate or deter their students / our child. That's something we need to consider also the punishment on their students / our child. Have we given "the lure of 'rewards to their students / our children if they do not command us or do we ban?
For example, if our students are always coming to school on time then we will give praise, or give a good value if they are always chores that we provide.

Reward function in children:
a. Educational value, because it shows that the behavior of children in accordance with what is desired.
b. Motivation, so that acceptable behavior is repeated.
c. Amplifier, for behavior that is socially acceptable.

Now all we hope that the actions already implemented some of the steps above. That sentencing on the students/children is allowed although not recommended for the purpose and the measure of punishment is appropriate.