As a way of adult higher education, self-taught examination has always been difficult. In adult education, self-taught students have to take more than a dozen courses, and each course needs to reach the qualified score line, which is not only because of the examinee's own knowledge level, but also because the examinee has chosen a major that is not suitable for him.
Everyone has a different knowledge base. Facing subjects that you are not good at is increasing the difficulty of graduation. Some candidates will have anxiety before the exam, and psychological factors are also part of the reasons that affect the exam results.