Let’s review what we’ve discussed about QFD in this chapter:
QFD is a product-planning tool that is used to translate business drivers (such as market size, brand loyalty, and disposable income of a customer segment) into the technical requirements of a product (such as seating & cargo capacity of vehicle interior).
Although QFD can certainly be used as a tool by an individual, its biggest value is as a tool used by a team. A team that works through product planning with QFD will emerge with a common vision of business drivers, priorities, assumptions and issues and questions to be resolved.
While the application of QFD to manufacturing is fairly standardized, no such standard exists for its application to use case-driven development. The general approach described in this chapter is to use QFD to transition from what the business requires, to what the user requires (stated with use cases), to what is required of the system. This transition is based on Wiegers’ levels of requirement types.
The use case community has given some attention to QFD as a tool for prioritizing use cases. But prioritized use cases can in turn also provide a means of prioritizing other aspects of software development (e.g., alternate product designs).
A useful way to think of QFD is as method of prototyping a project, allowing a team to run through a complete product development cycle quickly, from start (thinking about the business) to end (thinking about the final product that results from the business drivers). What-if analysis with QFD allows a team to explore the consequence of different priorities at the business driver or use case levels.