The first is that some people are quiet and don't like to get along with too many people. Such people like to be alone with themselves and enjoy quiet time. They saw the absurdity behind the excitement and didn't want to make friends.

The second is that some people have social phobia. They are afraid of socializing, often communicate with others and refuse to have sex with the outside world. They are afraid of the breakdown of their relationship with the outside world and all kinds of comments from the outside world. They are more likely to feel inferior and sensitive.

The third is that he lacks the material and spiritual foundation for making friends. He doesn't have enough money and time to maintain or run a friendship. He doesn't have the knowledge and vision of the same age and lacks the same topic, so he doesn't want to make friends.