He thinks that he is correct in the things he says about people, but most of the time he is incorrect.
One reason Holden is over-critical is that at some points just seeing someone he doesn't like can make him so annoyed he will leave the place he was in. Also he would begin to hate that person. One time in the story Holden runs into someone named Lillian Simmons. He knew her from his brother going out with her before. She invited him to sit with her and her date. He thought she was a phony. And just by seeing her he wanted to leave the place. “I certainly wasn't going to sit with old Lillian and that Navy guy and be bored to death. So I left. It made me mad though, when I was getting my coat. People are always ruining things for you.”(chapter 12 page 8). He blames people for things that they don't even do.
Another reason Holden gets over-critical is he finds little flaws in someone and begins to hate them. There is this one person he knew at Pency. His name was Ackley. He doesn't like Ackley because of these little flaws he has. “ That guy had just about everything. Sinus troubles, pimples, lousy teeth, halitosis, crumby fingernails.”(Chapter 5 page 39). He doesn't like Ackley because of these little flaws and thinks hes a phony.
The third reason Holden is over-critical is he thinks everyone is a phony if they don't agree with him. Like when he was going on a date with Sally. “Here's my idea. We can move up to Massachusetts or Vermont something and get married. I can get a job up there and we will have a terrific time! Wudda you say? Will you do it with me? Please!” (chapter 17 page 132) Sally didn't want to just jump in to something like that so she said no. And because she said no, Holden thought she was a big phony and started to not like her anymore.
Holden is always judging people and calling them phonies. But he really is the only phony and doesn't want to admit it so he blames it on other people. Holden is wat to over-critical. He points put the wrong on everyone else, instead of pointing out the truth about people. Holden Caulfield is a cranky over-critical teenager.