Quality Function Deployment: What, Why & How

Quality Function Deployment (QFD) has been known in the western world for the last thirty plus years, and, over that time, it has developed a checkered reputation. Companies that have spent the effort to really understand and apply it have achieved excellent results with it. Many other companies have merely dabbled with it or perhaps concluded that it is a series of complex matrices that take a lot of time with little to show for it.

One of the common issues with this latter group of companies is that they have not understood what QFD really is nor what it can do for them. If one explores the common issues companies face with new product development, one can better understand how QFD can fit into the development process to address these issues.

Issue 1: Current and future customer needs are not adequately understood. Innovation-based companies may focus on pushing a technology into the marketplace without truly understanding customer needs. Companies with existing products, assume they understand their customer needs. Or needs may rapidly evolve, but the company doesn’t recognize this situation. Marketing may understand the needs, but this knowledge is not passed on to the development team.

QFD Solution: Voice of the customer (VOC) – the effort to investigate and analyze customer needs is a prerequisite for a QFD effort. With QFD, VOC data is reduced into a set of critical customer needs using techniques such as affinity diagrams, function analysis, etc., defined and documented in customer needs data dictionary, and prioritized. This VOC effort is also the opportunity to recognized unfulfilled needs that can provide, at a minimum, competitive advantage, and, potentially, a break-through product or true value innovation. A basic principle of QFD and any other system is “garbage in, garbage out”. If adequate effort is not spent in understanding customer needs, the result of QFD, as well as the entire development effort, will be a less than optimum product.

Issue 2: The competitive situation is not understood nor adequately considered. Marketing may understand the competition, but this knowledge is not transferred to the team. No formal data collection or analysis is performed. This can lead to non-competitive or me-too products or products that rapidly lose their competitive advantage.

QFD Solution: Once customer needs are defined, the second major step with QFD is to perform competitive analysis. This includes not only analyzing current competitive strengths and weaknesses, but also considering future directions of competitors. It also involves mapping competitor’s positions against market and demographic characteristics and against key product characteristics to recognize threats and opportunities. This analysis is a key part of planning the new product.

Issue 3: Inadequate attention is paid to developing a product strategy and value proposition. There may be an implicit strategy understood by management, Marketing, or some team members, but not all team members understand this strategy, leading to suboptimal decisions. In the absence of competitive analysis and strategy, the team may want to exceed competitive product’s performance parameters in all areas, leading to a more costly product or a risky development project. The product may be aimed at the wrong market niche or miss the opportunity that exists.

QFD Solution: A third step in the QFD process is to develop the product strategy and value proposition. The objective is to get the “most bang for the buck” out of the development effort. This strategy needs to be explicitly defined, understood and agreed to by all participants. The strategy should reflect where the team will focus its development effort to achieve the customer value proposition (e.g. improvement goals, etc.). Use of related tools such as conjoint analysis can also help to validate the value of certain capabilities to the customer.

Issue 4: Product requirements and specifications are not carefully balanced against needs and implications. Marketing wants it all when they create a marketing requirements document. Specification target values can be arbitrarily established to exceed the competition without regard to cost or the value proposition. Inadequate consideration may be given to trade-offs among product parameters leading to additional cost and development effort. A requirement may be established because the developer thinks it would be a good idea.

QFD Solution: Requirements (technical characteristics) are only established in response to customer needs (stated or unstated but recognized). Technical benchmarking is performed to help understand the competitive position and establish appropriate specifications (target values). Trade-offs and cost drivers are analyzed in the interaction matrix. Risk and difficulty is considered in establishing specifications (target values). In short, there is a rigorous consideration of a variety of factors in objectively developing requirements and specifications.

Issue 5: Insufficient attention is given to developing collaboration and teamwork. Team members are assigned and thrown together in an Investigation or Feasibility stage, but frequently little explicit effort is given to develop collaboration and teamwork.

QFD Solution: QFD is a planning and decision-making methodology that is performed by the product team. It forces early communication, planning and decision-making among team members. It requires open sharing of information, overcoming the hidden knowledge that can otherwise plague a team. It bridges the gap between Marketing, Engineering, Manufacturing and Quality. Team member’s knowledge is “leveled” through this process. The initial product planning with QFD leads to rapidly developing collaboration, teamwork, and commitment to the product strategy and plan.

Issue 6: In the rush to develop a new product, inadequate attention is given to developing and evaluating concept alternatives. Traditional architectures, technologies, and concepts are assumed as the basis for the new product because time is short.

QFD Solution: QFD is oriented toward defining requirements (technical characteristics in a global manner – independent of a particular technical solution so that multiple concept alternatives can be considered and the best one selected. After the product planning matrix is completed, the QFD process includes a concept development and evaluation step with an emphasis on developing alternatives. The intent is to identify a more optimal, and perhaps even a break-through solution rather than continuing with the traditional concept used for past products. QFD provides a concept selection matrix using the requirements as a basis for decision criteria. QFD places an emphasis on innovation and providing innovative and exciting capabilities to customers.

Issue 7: Critical characteristics, process requirements and quality controls are not effectively linked. Frequently, designs are tossed over the wall to Manufacturing and Quality. They interpret drawings and define manufacturing processes and quality requirements without necessarily understanding the critical product and part parameters or critical processes. The result is that process and quality controls may not focus on the most important issues.

QFD Solution: QFD is a flowdown process with the deployment matrix, process planning matrix and process/quality control matrix. These subsequent QFD phases insure on-going communication, planning and decision-making among team members and between the Engineering, Manufacturing and Quality functions and with suppliers. Critical characteristics, process requirements and quality requirements are explicitly identified, planned and communicated. This assures alignment and commitment throughout the process and avoids some of the last minute quality problems that occur during launch.

When one considers the time required to address these issues (or the risks and sub-optimization if not addressed), QFD can not only save time and effort, but substantially reduce development risk and increase market acceptance and competitiveness. QFD, when performed with full understanding of the process and with adequate effort to collect and analyze the required data, is a powerful tool that addresses the shortcomings that are common in product development.

For further information on QFD, see the following links: Description of QFD (including examples) and Step-by-Step QFD Instructions