What is your veiw on parents who smack there kids as disapline was you ever smacked as a kid growing up

My parents did it and it evolved into being just an outlet for their anger where they'd hit you for any reason when they were angry. It was like they couldn't control the ferocity and just let loose. They said it was for our own good but kids aren't stupid and can see what's going on. Ultimately it backfired because my sibling who have kids could never trust them to leave their kids alone with them. So my parent never had personal time with their grand kids and were very upset about not being trusted.