Following the article, the education system could be a reason of Know-It-All and it could happen to anyone. The self-cognition and the sense of self-worth were lowered due to the excellent students who get top grades. People started to realize that "the accumulation of facts and information equals power" through the experiences in school. And from the fact 'top graders always have right answers', the expectation of rewards never stops, even after they finish school and work in society. It was very interesting that anyone could have a possibility of know-it-all with this reason above.
I have a friend who has this behavior and more over his personality is very straightforward. Most of time, he was always being know-it-all and pretended to be smart. We listened to him but as time goes by, we tended to ignore him, in unnoticeable steps. It seems to he doesn't need any help or suggestions from others since he pretends he knows everything. The ways of 'how to deal with a Know-It-All' was good to know and very helpful. I want to try it later. :)