If your goal is to get all 10 points in your upcoming exam, but you spend four points a day playing soccer with your friends. Playing soccer is considered a waste of time. However, if you have your mind set on becoming a national level soccer player, practicing your skills one day is not a waste of time. If you write down "studying at school" from 9-10 am, is this time not wasted? The answer depends on many factors. If you often talk during class and don't pay attention when studying, the result is that you don't learn anything, and you also waste an hour of wasted time even if you "study at school". Activities like sleeping and bathing can be a waste of time if you spend too much time on them.