In my opinion a good teacher has to train every day for himself and does not need to please a student.
A good teacher walks his way and the student may accompany him some time and learn from him. For a real teacher Karate has become a part of his daily life,
it is nothing extraordinary. He walks his way no matter what happens.
A student may follow in his footsteps and try to pursue this way. In many places on the way however some students won’t be ready to incur strains or won’t recognize the footprints und therefore can’t follow the teacher anymore and stay at this place respectively.
Other students will follow the teacher further and the further along the way one walks the closer one gets to his teacher because the further one gets up the harder it gets. Eventually it will become a collective climbing tour where the teacher still leads because he has already made some mistakes on the steep face and knows the unsafe places. Together with his student it gets easier and eventually the student may take a different path and choose a different peak of the mountain massif as his goal. Then student and teacher will wave to one another from time to time while ascending.
In my opinion health and Karate are one. Because one knows how healthy Karate is one trains every day for oneself.
A good teacher knows how to cope with injury, knows the anatomy of the human body (for better or for worse), knows psychological pitfalls that emerge and knows how to cope with them (regardless wether through Zen, Psychology, Christianity, Daoism, Shintoism, etc.). He challenges his student to his limits and sometimes beyond and is then there for him to show new possibilities. He lets the student come to him and doesn’t chase him because only when a student is really willing to learn he can teach him something that isn’t gymnastics.
A good teacher is healer, psychotherapist, priest, best friend and worst foe all in one person.