First of all, as a tutor of remedial classes, in fact, many interests are not really guaranteed. Because the training institutions won't prepare for you like those teachers in public schools. Compilation is a guarantee, even if you may not have enough to eat, you will not starve to death. Although the salary of tutors in remedial classes may be higher than that of teachers, I think tutors in remedial classes face greater risks.
Secondly, as a teacher, you will have some occupational diseases more or less. You will be fine when you are young and strong. You may be in good health in your thirties and forties, but after working for many years, some people begin to have various old diseases. If you are a teacher in a remedial class, you may only be expelled if you have physical problems, but if you are a teacher with a preparation, you will basically not encounter such trouble.
Moreover, the tutors in training institutions are also very tired, because you have to prepare lessons, and some institutions are understaffed, so you have to teach students with high intensity. I have met several training teachers in public educational institutions, who once dragged their sick bodies to class, and some even fainted directly in the office. Especially if there is an exam, these teachers basically have to stay up all night to sort out the papers and send the answers online. ...
Therefore, without a strong body, it is really hard to be a tutor in a training institution. And even if you are in good health and often stay up late, your body will have big and small problems because of excessive fatigue. Unless you become a tutor, you can be a manager, you can own shares or start your own business, otherwise being a tutor all the time is actually eating a youthful meal.