Think of it like this: If a student athlete only practices during PE, are they going to reach their full potential like they would if they dutifully went to practice after school on days they are scheduled to have practices? No. Would students in band or symphony learn to play well if they don’t practice after school and on the weekends? Probably not. And I would hazard a guess and say more than likely not. If a student artist only learns about various artistic techniques in class and doesn’t practice them outside of class, then will they attain mastery?