The legal and the health professions are unique with regard to expectations. When you utilize the services of a litigation attorney you may have expectations that are different than what you should have. You of course expect to win your case. However, the attorney's expectations are different. He or she expects to argue your case as effectively as possible.
Attorneys hope to win a case but they know that there are factors out of their control.
Their client may not have a good case. The judge and jury are variables that always have to be considered. These factors and many more are why attorneys don't give guarantees. In the health field a very similar situation exists. The doctor, whether medical or chiropractic, would like to see you get well.