this is a good philosophical question. I don't have a good answer, but if you look into theories about hedonism you will most likely disagree with it. Living life to gain the most pleasure possible for ourself seems weak. I don't know it may be our willpower to live life meaningful and not "cheaply" that makes a life of pleasure, sex, and drugs not attractive.

I think a lot of our willpower and courage in life comes from our Super Ego. So because of that we want to stay away from things that hurt us and make us weak, and instead be good people and help good people. Also nature and nurture are huge...

Also, Survival of the fittest. One of my teachers had an unlikely theory but a good thought test. He believed that over the course of millions of years, early humans with undesirable human qualities who were selfish, violent, and in it for themselves all killed each other or died off. Humans the helped each other and cared about their offspring and their well being as well as others lived and passed on their good genes.

I think there's a million different answers to this question and it makes one think for sure