Teachers are always sacrificing and selfless. I think this is one of the best traits for teachers. I find it hard for someone to be a teacher if they were selfish. They probably wouldn't choose this type of job since I feel teaching has a lot of work. You're not just working during the day to teach students but after hours you have to think of what to teach, grade papers etc. The biggest reward you get is seeing these students do well and maybe come back to you in the future and say thanks at least if you have those experiences. I know some teachers that get some students that visit them few years later which makes the teacher happy. You're working hard for your students all the best!