Mitch does change as the book goes on (especially towards the end) because he is learning many life lessons from Morrie. Mitch really valued money and material things but he eventually learned from Morrie that these things are not what is important in life. Mitch has learned that he needs to live his life to the fullest. He realizes that he wasted a lot of time working and this needs to change. In addition, Morrie teaches him not to live a life that is full of vanity. Mitch admires Morrie and wants to live his life the way Morrie lived his-full of love and acceptance.
In the book "Tuesdays with Morrie" Mitch was not very responsible about visiting the people that he cared about. He had let too much time pass between Morrie and himself and he had promised him he would visit and not come back for years.
Mitch recognizes this in himself and begins to make sure that he visits Morrie consistently every Tuesday. As Mitch watches Morrie physically dying before him but still having his sense of humor and dignity, Mitch begins to question his own life and the things that he did not do because it was easier to make other choices.
Morrie teaches Mitch how to truly live and embrace his life. Mitch changes because he has more appreciation about his life and decides to pursue other dreams he had once had. He later writes the book Tuesdays with Morrie.