In my early teenage years I was bullied and sometimes that takes a lot of fighting instinct out of you. The urge to stay quiet and not attract attention is very strong. By my mid to late teens I was a very angry individual and fought more.
As I grew older and more social I was invariably among the older members of my social group and it was backed up by a lot of responsibility towards them and then I'd have their back in tense situations, pervs at clubs etc
But I have to admit I still defer to talking things out than throwing the first punch,