It’s an artificial environment
Next time you find yourself in a school, take a good look around. Notice anything unnatural? The benches are placed around in such a way that makes people form tight groups or cliques. There is the popular kids’ bench. The beauty queens’ bench, the nerds’ corner. Moving from one group of people to another feels a bit awkward or weird because everyone seems to have their own territory.
You see the same people everyday
Unless there are more than 2000 students in your school you are going to have a hard time looking for different people to talk to. I used to be in school with no more than 1000 students and that included students ranging from ages 12-18 so my options were very limited. On top of that, I had to encounter the same haters, the same friends and the same girls blah blah blah … you get the point, it’s very tiring and boring.
Introverted people have a hard time fitting in
If you are the type of person who likes to read different topics on blogs online, reading books or watching videos of intellectual people having discussions, chances are, you are going to feel a bit lonely because nobody seems to be engaged in these types of hobbies. For instance, most guys in my school only knew how to talk about sports and politics which are topics that I had no interests in and I had trouble making interesting conversations so most of the time I had to fake interest or make them talk more about their selves to keep the conversations going and then I would resume being myself whenever someone who’s mind does not revolve around sports and heated politics discussion. Another problem that introverts face is the fact that they have to make small talk with other students which for them, is pointless because they seek more meanigful interactions. Soon enough, this will drive introverts to great dissapointment if they can't find anyone that matches their personalities and so they give up with people or seek to expend their energy on other activities.
Schools in general might teach you how to study or how to write and do maths well, but one thing that will not help you improve in your life is your social skills because the school system doesn’t really care about it. They don’t really care about your personality or the ability to communicate with people at any time or place. They just want parents to pay them money so their children can be “educated”.