What causes self centered behavior

I don't cut in line, i don't cheat on my partner.It's a trait, a behavior which causes them to focus on themselves and push everyone else out of the picture.It really is a cause and effect situation.You can see this manifested quite clearly on social media.For example, if you take a look at people with narcissistic tendencies, you'll discover that although there are genetic factors that come into play, a huge.