The school system, as we know it, is and has been shaping students to fit the system in which they live. Throughout this process, the students are forced to learn (mostly memorize) subjects in which they do not have any interest whatsoever and because of this they can't score high in school. It is as if our brains are trying to avoid information, which is not interesting as much as possible. But when there is something of interest it is very easy to collect and comprehend that information.
Let's assume that you are a programmer and you are greatly amazed by that. You love solving problems and developing software. You read lots of documentation and contribute on other people's projects without even having to worry about "remembering" what you're reading. Everything is easily understood and there's no issue with that. But when you have to learn about politics and how the system works, it appears as a cancer to your eyes because you have no interest in it. There's no will to collect that information and therefore you score low in that subject.
Now my question is: Why can't we learn what we don't like? Why can't we learn what we're not interested in?