This principle, which holds that the origin of the theory Expectancy Disconfirmation or Disconfirmation Model, a theory that is important. And widely used In explaining the principles of ีusers satisfaction is that the concept of satisfaction or dissatisfaction. By comparison Between the expectations of users, an application that has a fair trial. Which occurred during Before using the fact that the user is active. Users will be assessed Compare between hopes and feelings. Get real And creating a situation three reasons.