It depends. Solemnised, ritual punishment such as paddling or caning can have bad side-effects, certainly, if applied improperly.

A light cuff across the head (known in our family as a 'Gibbs') used as a reminder or wake-up call can be handy. It can prevent kids digging themelves into a 'no TV, no tablet-time, no dessert' situation, or stop a developing bad habit or 'tic' before it starts.

On the other hand, there are some litle swine out there who will do exactly as they please in the teeth of every kind of couselling, in any environment and no matter how much they are respected, listened to, stimulated or encouraged. The only way to modify the behaviour of kids like these is to let them know that you are, if necessary, both willing to hurt and capable of hurting them. Pain and the threat of pain is how they contol other kids, and it's the only measure of power they understand. They are the kids who grow up to be gangsters, CEOs, politicians or dentists.

Just bear in mind that under every ordinary, normal, decent, kindly, law-abiding person is a selfish, thuggish, criminal-minded layabout who's only being good because they're also a coward.