Systematic learning (especially of the institutionalized kind, the way it’s done at schools) doesn’t work - the principal method of learning is being exposed to some new info which you connect to what you already know in a creative way, educational institutions always try to do the creative work for you and that’s why the process is bound to fail. Learning is always spontaneous and almost always comes from unserious and unusual channels. That’s why a week of motivated research can get you to learn more than years at school.