Changing Requirements
We, as software engineers, know full well that requirements change. Indeed, most of us realize that the requirements document is the most volatile document in the project. If our designs are failing due to the constant rain of changing requirements, it is our designs that are at fault. We must somehow find a way to make our designs resilient to such changes and protect them from rotting. (Martin 3-4)
Work Cited: Martin, Robert C. Design Principles and Design Patterns. objectmentor.com, 2000, http://www.objectmentor.com/resources/articles/Principles_and_Patterns.pdf.