From Alvin Rabushka’s Thoughtful Ideas blog quoting Confucius: “I do not instruct the uninterested; I do not help those who fail to try. If I mention one corner of a subject and the pupil does not deduce therefrom the other three, I drop him.” Chapter VII, Verse 8 (James R. Ware).
This is a fence that most teachers walk every day. Confucius set a high standard and I suspect he seldom, if ever, waived. Teachers care! But each has a point at which she or he is obligated to move on, to move past the student who just will not try. Policy makers and administrators know this and make similar decisions regarding employees and teachers, however, they are in denial when it comes to the classroom. Schools have limited resources. Trade-offs will be made. Accept it.