Well, you have probably noticed that the general tendency is to blame the teacher when the exam results are poor. The idea is that the teacher was unable to present the material properly for students to understand.
Yet, what is important to highlight is that the studying process which involves two people who need to be interested in what they are doing. Surely, teachers should make their classes as diverse and interesting as possible. However, students should make effort to acquire new knowledge as well as work a little harder in case they do not understand something.
That is the reason why it is not quite reasonable to state that it is someone’s fault when a particular student fails at the exam. What is significant is to learn from those mistakes and to try harder next time. Besides, we all have different studying patterns and techniques which is why some learning method might work for you but it will not work for your classmate, for instance. This aspect should be taken into account as well.