I am abhor the practice of beating/whipping a child. I knew many that did it when I was growing up and some that still do. I am not against the very rare swat on the backside of a young child that is throwing a fit or behaving really badly (hurting another child, throwing objects, screaming tantrum, etc). This is only to get their quick attention and is done with an open hand and not done any harder than you would if you were playing or roughhousing with your child. Never to inflict pain or harm. I am a firm believer that using any sort of implement to strike your child should be grounds for criminal prosecution. No belts. No switches, No paddles. Wrong, wrong, wrong.
But if we observe other species of animals (mostly large mammals) that have similar social structures as humans (apes, monkeys, big cats, canines, elephants, even cetaceans and pinnipeds) and observe the behavior of parent animals disciplining and correcting their youngsters we will see that animals often have to show some sort of force and dominance over their young to train them in the expected social manners of the family unit or pack or herd, whatever. This discipline and dominance is NOT done with any malice or true anger by the animals. It is done in a way that gets the attention of the youngster but without harming them or scarring them emotionally and breaking their spirit.
Sadly, I have seen many JW children with broken spirits because their awful parents used "the rod" scripture as an excuse to have open season on their children. It is disgusting and shows the lack of love and lack of intelligence these parents have. What I know for sure, those parents get paid back tenfold for their abusiveness by their children one day.