Your student doesn't believe in his/her skills? Is studying sistematically but always thinks it's not enough? You, however, see his/her progress and how much work he/she puts into learning. It's possible, that he/she lacks of self-confidence - maybe that's why he/she can not realistically assess his/her capabilities.
It happened to one of my students. She was preparing to pass the A2 exam in language school. In the first e-mail she wrote, I noticed that she was overhelmed by lessons at the academy. She asked me for extra classes, during which she could revise the knowledge gained at school. In our first meeting, she told that it's first time in her life she learns English what makes her feel little lost. During the same lesson, she told me that other students in her group are "good students". She considered herself as the only "bad student" in the whole group. I told her to don't worry and keep learning, so with the time she would gain more skills and confidence.
This was the wrong thing to say. My approach to ignore this signal was wrong. During next lessons I've noticed that she still often repeats the "fact" of being the worst student in the group. I decided to take action. I understood her feeling to be lost and confused. This is a normal thing, when you start to do something completely new. But I was sure, that being the worst student was not true. I started to look for a cause of these thoughts. After a few lessons she admitted, that in the academy she feels a lot of pressure from the teacher, who is demanding and expecting visible progress. That's understable - the teacher's job is to prepare his/her students to pass the exam ans is doing it the best he/she can. The grades and gained points matter. The topics are passing fast, without the possibility to review or repeat. For this particular student, this situation was really hard to handle. She could not meet the teacher's expectations and develop her skills in the same time as the rest of the group.
We started to meet twice a week for two hours. I paid more attention to make her feel comfortable. We both knew, that the academy teacher is demanding, so we worked hard to meet her expectations. I thought, that the stressless atmosphere and learning without any pressure of time can help my student to grow - and I was right. We took the time to review topics from academy's lessons and learn new. I gave her all the necessary time and patience. After a few lessons I've noticed that she is much more confident and enthusiastic to learn. I started to see the real progress in learning. Step by step she is building self-confidence. Thanks to this, she started to get better grades at the academy. She is having more and more points with every test.
This situation taught me how important is student's self-confidence. How much more he/her can achieve if believes in him/herself. Now I can better understand what it means to be a private teacher and how I should work with my next students. I have learned that my work and the way I do it has a real impact on the studen's achievements.
It's my job too to help the students believe in themselves!