>>72855701. Bad parenting. Abusive parent, missing dad, addiction, etc. A bad home environment will usually create a bad person, unless that person is naturally good and functional.
2. Being in a bad area. This means you were expose to people who didn't have good parenting or solid family life. This means growing up around people who didn't have high aspirations. This means being in an environment where you simply don't have proper or reasonable social nerms that would clue you in on how to act like a functional adult.
3. TRAUMA. This is the big tipping point. Phil is bipolar. Bipolar is the brain's inability to properly restrain emotional reactions, and the inappropriate usage of flight or fight mechanics. Most people have some form of bipolar, but learn to either cope with the phases or just naturally deal with it. As in any joe off the street could be diagnosed with mild bipolar. For it to cross over the boundary, you need a traumatic event that messed you up for a significant amount of time. For example, Mauro Ranello has that one friend who died and it messed him up hard. It needs to be a significant event. He's been a bitch for a while, so it most likely happened during his adolesence. If someone died, he got raped, or someone got raped because he wasn't able to stop it, then that would set him off pretty good.
If you have to ask, you're most likely not going to be someone like him.