It is rewarded, simply by the fact that they then have to put less effort into the class. Why should it be graded? The point of the class is not to learn quick

It is rewarded, simply by the fact that they then have to put less effort into the class. Why should it be graded? The point of the class is not to learn quickly and effortlessly, but to learn the material completely. If by the time the class is over the student has learned it well, they should get a grade that reflects that learning. I mean, by your logic, should we give extra credit to the students who never show up to office hours in college, since clearly they're learning it 'faster and (more) effectily(sic)'?