Yes, of course, every one that sees the futility / error of their ways and moves on; to do something with their lives, is a success.  However, I found, in my time, that the fastest and most long lasting cure; was when the people themselves woke up and changed. The catalyst for that was ( when and if it did happen ) different things for different people, sometimes having a child and being needed by somebody to provide for them; did it. Sometimes, the death of a family member, so they moved up the chain of responsibility did it...........but if a helping hand does the trick; then why not. There are some though, that are just bad to the bone.......as I'm sure we all know.......only too well.