There is also context to look at this in terms of the animal kingdom. Wolf's nip their pups behind the ear when they break certain pack rules. The mother isn't being cruel or vindictive. And they have the verbal capacity to communicate such concepts as right and wrong, so it's not that they have an inferior method of conveying their basic rules of society.

Anyways don't take that out of context it's just an example.

Sometimes a physical action is required to reinforce the notion that something is not to be done.

You engage verbally with adults because your brain has developed to handle complex reasoning. This isn't the case in small children. The naughty step just doesn't quite have the same effect as a smack out of fear to let your kid know don't run out in front of traffic because you will get killed.

I wouldn't call that parent cruel for wanting to ensure their kid never did something like that, because they are worried that the child doesn't grasp the concept of death as a permanent state of nothing.

As a child grows you then reason more.

Look both can work, saying one is superior is like saying their is a best way to teach kids in school. Which is exactly why dyslexic kids were made to feel like idiots in previous decades because they were not being taught in a way that suited how their brains worked.

In short the word is complex, and I keepy mind open to all methods based on the outcome. As I said I got smacked as a child, and I certainly would not use the terms physical violence or cruel to describe how my mother brought me up. Just saying.