That used to be my approach, but time and time again, I'd find them faux-apologizing just to turn around and continue doing it. So I decided to flag and then explain. Nothing gets the point across better than "Hey man, quit shitting on people's posts and begging because I will flag you for it."
It really helps correct people's behavior, all it does is negate that problematic post and presents an opportunity for them to think about. I don't mean the flag in an offensive way, but in a protect-the-platform-plus-here-is-a-learning-opportunity way.
your approach can be right with some kinds of users but not all of them
because the people who have an original good manners and behavior, have the initial intention to use the platform properly and respect the users but they just need someone who put them on the right direction and they will start to be good users automatically.
they just need someone to learn them.
but the kind of people who have an original shit behavior will never change and the downvote will never change them or make them respect the users and they will keep acting badly whatever happens.
this point of view is based on personal experiences of me and I'm really happy that I see many users that was acting this way and after I advised them, they started to change their way of using the platform and now they are growing more and more and providing good content quality through both posts and comments.
and I become happier as I see them growing more and more