Why do some people say correspondence is useful and others say it is useless?

Conclusion: Correspondence education is useful.

It is useful to upgrade from junior college to undergraduate course by correspondence. In many countries, the vocational qualification certificate requires a bachelor degree or above. For example, the current judicial examination requires notaries, lawyers, judges and prosecutors to have a bachelor's degree or above, and they can all pass correspondence certificates. Anyone who admits that communication is useful agrees with it. Similarly, it is generally not recognized that most correspondence assignments think that the gold content of correspondence is not as good as that of undergraduate courses, which is one-sided.

Introduction to correspondence courses:

After being admitted to colleges and universities through the national adult college entrance examination, courses of corresponding majors are generally offered in a planned way within three years. At the same time, classes are held on weekends or in winter and summer vacations, with teachers guiding the study, and then the teachers in the class give the exam and pass. It can be said that graduation is basically simple as long as you pass the adult college entrance examination.

Refer to the above? Baidu encyclopedia-correspondence course