What is QFD and When Do We Use It?
Quality Function Deployment (QFD) is a Lean technique to design processes or products according to customer requirements.
The method was developed in Japan in 1966 and was aimed to help transform the voice of the customer into engineering characteristics for a product.
Here's how the author of the method Yoji Akao, described it:
"A method to transform qualitative user demands into quantitative parameters, to deploy the functions forming quality, and to deploy methods for achieving the design quality into subsystems and component parts, and ultimately to specific elements of the manufacturing process."
QFD Advantages and Benefits
- QFD is a powerful tool for prioritization that combines several matrices into one concept (house-like structure).
- It can be easily used for planning products and services as an effective customer-driven process.
- It starts with the voice of the customer, which becomes the basis for setting requirements.
- QFD provides documentation for the decision-making process.
The technique helps to:
- turn customer requirements into specific offering specifications.
- prioritize offering specifications and make trade-off decisions based on ranked competitive assessment and weighted customer requirements.
Quality Function Deployment is also a system for design of a product or service based on customer demands. It involves the entire company in the design and control activity.
The method is also called “the house of quality” matrices. This simple house-visualization graphically displays the results of the planning process.
The matrices are built by teams from different departments. This figure is the QFD diagram and it includes 5 “rooms”:
- What or Wants means customer needs, requirements, and priorities that form the far left wing of the house.
- Competitive Assessment part that compares customer priorities with appropriate marketplace offerings, across key competitive deployments. This is the right wing of the house.
- How block - the offering’s technical design features, functionality, and characteristics to meet the customer requirements, that form the attic.
- Design Relationships describe the interrelationship between the design features and this is the roof of the house.
- The Foundation that uses benchmarked target values as objective measurements to evaluate each characteristic. This part forms the basement of the house.
What does the QFD process mean?
The approach is used to design an error-free process or any product.
It's usually started with planning the development and go through key stages to reach a deeper understanding of the required process control and quality.
The 4 stages are:
- Product Planning QFD.
- Component Deployment QFD.
- Process Planning QFD.
- Quality Control QFD.
Each stage in this 4-steps approach is related to the previous one.
Thus, Quality Function Deployment is the way to design processes that produce products or services that satisfy the customer.