I think the main reason is that China has a large population. The huge population leads to fierce competition. Secondly, I think what students have learned in college can't meet the needs of society. The society is developing continuously, but education has not kept pace with the development. Thirdly, I think the reason may be the quality of college graduates. Even if many of them get bachelor's or master's degrees, in fact, they don't meet the real standards of qualification at all. Qualification standards include not only academic knowledge, but also social work experience and appropriate self-worth assessment in order to integrate into the real society. The above is my general idea.