Quality Function Deployment [QFD] is a bad translation of a good reliability technique for getting the voice of the customer into the design process so the product delivered is the product the customer desires. In particular it is applicable to soft issues that are difficult to specify.
Why use Quality Function Deployment?
The Quality Function Deployment method helps pinpoint: 1) what to do, 2) the best ways to accomplish the objective, 3) the best order for achieving the design objectives, and 4) the staffing/assets required to complete the task.
When to use Quality Function Deployment?
Quality Function Deployment is a major up-front effort (as is the case with most Japanese techniques) to learn and understand the customers requirements and the approach that will satisfy their objectives.
Where to use Quality Function Deployment?
The Quality Function Deployment methodology is used as a team approach to solving problems and satisfying customers beginning with a listing of customer requirements, converting customer requirements into engineering characteristics (the house of quality), converting engineering characteristics into parts characteristics (the house of parts deployment), converting parts characteristics in process characteristics (the house of process planning), and finally converting the process characteristics into production characteristics (the house of production planning). As with all Japanese techniques the up front costs are high and many clever graphical tools exist for transferring information with the intention of decreasing costs downstream while satisfying customer's needs.
These definitions are written by H. Paul Barringer