In Chapter 4 , we introduced the Tailor-Made Requirements Analysis Process. Although there is much that can be learned from the research, analysis, and discussions outlined in that chapter, quantifying capabilities (i.e., how much is enough) as well as identifying unspoken nonfunctional requirements often remains challenging. Furthermore, as you will see in Section 3, metrics are helpful for improving the overall observability of your design. Metrics provide important tools for monitoring and evolving your architecture over time as the variables driving design decisions inevitably change, and the system’s needs evolve. Consequently, business metrics often become extremely valuable for you as an architect.