Discipline Versus Punishment
Punishing children for attempting to get their needs met does not stop them from needing to get their needs met. If a child is attempting to get their need for freedom met by being with people of whom the parent doesn't approve, that freedom need does not go away by punishing the child. In fact, often punishment restricts the freedom need even further, making it more likely that the child will engage in more severe and desperate ways of meeting their freedom need.
For example, if the child is grounded for being with people the parent disapproves of, then they may end up disrespecting the grounding and attempting to go out anyway. Then, it will become necessary for the parent to become more severe in their punishment to attempt to gain control.
The interesting thing about control is that we really don't have control over our children. We cannot be with them 24/7 and thus, we really don't know what they are doing when they are out of our site. We may think we are controlling them by grounding them, but are they sneaking out? If not, what happens when the grounding is lifted?