As more use cases and scenarios are developed it is necessary to make the model homogeneous. This is especially true if multiple teams are working on different parts of the model. Classes are examined to determine if:
Two or more classes may be combined
One class should be split
A class should be eliminated altogether
Consistency checking must be performed throughout the life cycle of any project. Consistency checking is needed because several views of the system are under development in parallel and care must be taken to ensure that the models stay in synch. There are three ways to perform consistency checking: scenario walk-throughs, event tracing, and review of the model documentation.