Why go from an A to an F or a B to a C? That sucks. Why not level-up? At Princeton, they've actually experimented with this, with quizzes where you gain experience points, and you level up from B to an A. And it's very powerful.
Y en Princeton han experimentado esto en realidad en cuestionarios en los que uno gana puntos de experiencia y uno sube de B a A. Y es muy poderoso.