John, I have learned that the stars are brightest when the night is darkest. Nothing works perfectly, but that doesn't not mean a teacher shouldn't try all the time.
Teachers are people of hope.
When a teacher stops having hope, he or she can no longer have faith and belief, will find it easier to quit or escape or cop out or stop. And, the situation will then indeed become hopeless, that is, discouraging and disappointing. For me, I am a man of endless second chances, eternal hope, whose efforts end only, as Yogi Berra would say, when the fat lady sings, and most likely maybe not even then. Miracles happen in the classroom, but not by themselves. You have to look for them, want them to occur, and work hard for them to occur.