I once argued to my twins' biological father, gladly absent for many years, that you couldn't make the infants/toddlers go to sleep. It wasn't possible. They sleep and wake when they want, and if there was some trick to it, I would have heard about it somehow.
He abusively assured me it was. And by golly he was right. If you, in fact, spank them repeatedly every time they open their eyes, they will indeed learn to keep them shut! Toddlers in diapers.
The abuse had come to a head. It involved them on a scale that would tip if I let it continue. I was gone very shortly after.
My children were going to be loving, respectful young men. They were going to be raised to obey, out of fear of disappointment, not because of fear itself.
Every disciplinary action made should involve a self-imposed question. "Am I angry?"
Your children will learn from actions made out of thought based on 'I'm doing this to protect you. I'm trying to teach you right from wrong. I don't want you to get hurt.'
Anger teaches 'If you disobey, I'll be the one that hurts you.' Fear.
Anger and fear will be the driving force of young developing minds trying to learn their way in the world.
It will breed.
There will never be any tolerance from anyone using fear to teach my kids an example. Fear of failure, fear of disappointment, fear of getting hurt are natural fears. There is no reason to install fear of pain from a parent. I do not want my children to fear being hurt by me.