The benefits of using an instance approach come to demand access from this method to be a task-centric and user-centered perspective. Compared to function-centric methods, use an instance method to make users more clearly recognize that the new system allows them to do. If the code written by the developer has never been used, this will be frustrated. With examples, the resulting functional requirements clearly specify specific tasks performed by the user. Use example technology to prevent "isolated" function - these features seem to be a good insight in demand acquisition, but no one uses them, because they don't have truly link with user tasks. In terms of technology, the method of using examples also brings benefits. Using an example view reveals the domain object and the responsibility between them. Developers use object-oriented design methods to convert usage instances into object models. Further, when the business process changes over time, the task embedded in a particular usage example will also change accordingly. If you track functional requirements, design, encoding, and testing instances of their parent class - user comments - then this is easy to see throughout the system
