What must a kid avoid in order to "turn out ok"?

When a kid starts hanging out with a goth group, or whatever, many times the parent will ask “Should I intervene”? Many will then try to calm them down, saying that they themselves were once a goth kid, and they turned out alright. But what must the kid avoid in order to “turn out alright”? If the kid doesn’t just wear the makeup, but is cutting, is it ok so long as they don’t kill themselves and eventually join the Peace Corp? Is a heroin addiction ok if they eventually become a well-paid and respected lawyer/doctor? Sacrificing a goat?

For example, when I was a teen, I was very depressed. I became suicidal, and did some self-injury. When I was 21, I tried to kill myself. Now, I think I’ve turned out pretty well, but would the journey be too harsh for a parent to say “it’s just a phase”?

So, what must a kid avoid in order to “turn out ok”? From the kids point of view? What about the parents point of view?