In the past, our view of cohesion was much simpler than the REP, CCP, and CRP implied. We once thought that cohesion was simply the attribute that a module performs one, and only one, function. However, the three principles of component cohesion describe a much more complex variety of cohesion. In choosing the classes to group together into components, we must consider the opposing forces involved in reusability and develop-ability. Balancing these forces with the needs of the application is nontrivial. Moreover, the balance is almost always dynamic.
