Abuse is abuse, plain and simple. It shouldn't be justified. Just because you're incapable of parenting properly doesn't mean you should physically or verbally abuse your child.
All it really does is set your child to cut contact with you, leaving you to die pretty much alone.
You get better results incentivising someone to do well, not making them scared of doing poorly, it just harms them later in life.
Totally not speaking from experience here.