QUALITY FUNCTION
DEPLOYMENT
Getting from the voice of the customer to technical design specifications
 Quality Function Deployment
 Voice of the customer
 House of quality
QFD: An approach that integrates the “voice of the
customer” into the product and service
development process.
QUALITY FUNCTION DEPLOYMENT
•Quality Function Deployment (QFD) is a technique introduced in
Japan by Yoji Akao in 1966 and initially used extensively by Toyota
According to Akao (1990), QFD "is a method for developing a
design quality aimed at satisfying the consumer and then translating
the consumer's demand into design targets and major quality
assurance points to be used throughout the production phase".
•It is a structured procedure used to translate the expressed or
perceived needs of customers first into specific product or service
design characteristics and features, and then into process and
operational characteristics.
Strengths and Benefits of Quality Function Deployment
•QFD seeks out both "spoken" and "unspoken" customer
requirements and maximizes "positive" quality (such as ease
of use, fun, luxury) that creates value.
•Instead of conventional design processes that focus more on
engineering capabilities and less on customer needs, QFD
focuses all product development activities on customer needs.
•QFD makes invisible requirements and strategic advantages
visible. This allows a company to prioritize and deliver on
them.
Strengths and Benefits of Quality Function Deployment
•Reduced time to market.
•Reduction in design changes.
•Decreased design and manufacturing costs.
•Improved quality.
•Increased customer satisfaction.
Usage of the Quality Function Deployment method
Applications
• To prioritize customer demands and customer needs, spoken
and unspoken
• Translating these needs into actions and designs such as
technical characteristics and specifications
• To build and deliver a quality product or service, by focusing
various business functions toward achieving a common goal of
customer satisfaction
QFD has been applied in many industries: aerospace, manufacturing,
software, communication, IT, chemical and pharmaceutical, transportation,
defense, government, R&D, food, and service industry.
Limitations and Disadvantages of Quality Function
Deployment.
•As with other Japanese management techniques, some
problems can occur when we apply QFD within the western
business environment and culture.
•Customer perceptions are found by market surveys. If the
survey is performed in a poor way, then the whole analysis may
result in doing harm to the firm.
•The needs and wants of customers can change quickly. A
comprehensive system and methodical thinking can make
adapting to changed market needs more complex.
Assumptions of Quality Function Deployment.
• The market survey results are accurate.
• Customer needs can be documented and captured, and
they remain stable during the whole process.
Four Important Points to Understand Before
Implementation of QFD
1. No matter how well the design team thinks it
understands the problem, it should employ the QFD
method for all design areas. In the process the team will
learn what it doesn’t know about the problem.
2. The customer’s requirements must be translated into
measurable design targets. You can’t design a car door
that is “easy to open” when you don’t know the meaning
of the word “easy”.
Four Important Points to Understand Before
Implementation of QFD (con’t)
3. The QFD method can be applied to the entire problem
and/or any sub-problem.
4. It is important to worry about what needs to be
designed and, only after this is fully understood, to worry
about how the design will look and work.
What QFD can do …
Our cognitive capabilities generally lead us to try to
assimilate the customer’s functional requirements
(what is to be designed) in terms of form (how it will
look).
These images then become our favored designs and we
get locked into them. The QFD procedure helps us to
overcome this cognitive limitation.
The Quality Function Deployment (QFD) Technique
1. Identifying the customer(s)
2. Determining customer requirements
3. Prioritizing the requirements
4. Competition benchmarking
5. Translating the customer requirements into measurable
engineering requirements
6. Setting engineering targets for design
Step 1: Identifying the Customer(s) –
Who is the customer?
In addition to the person buying the product, the
customers of the design engineer would also include the
manufacturing and assembly engineers and workers. (or
anyone else downstream of the design process).
Step 2: Determining Customer Requirements –
The goal is to develop a list of all the customer
requirements (made up in the customer’s own words)
that will affect the design. This should be accomplished
with the whole design team, based on the results of
customer surveys.
Kano Model - used to understand the importance of design
characteristics to a customer
•Basic Needs
•Performance Needs
•Excitement Needs
Basic Needs
Some of these needs are so fundamental, they are often not expressed by the
customer. However, they are crucial and must be identified.
The best that we can expect by meeting these is a consumer that is not unhappy.
Performance Needs
These provide increased satisfaction as performance improves. They are generally
expressed by the consumer.
Excitement Needs
These cause immediate happiness. Needs of this type are typically not verbalized.
Creation of some excitement features in a design will differentiate your product from
the competition.
Customers’ Requirements



Normal Requirements are typically what we get by just
asking customers what they want.
Expected Requirements are often so basic the customer
may fail to mention them - until we fail to perform them.
For example, if coffee is served hot, customers barely
notice it. If it's cold or too hot, dissatisfaction occurs.
Expected requirements must be fulfilled.
Exciting Requirements are difficult to discover. They are
beyond the customer's expectations. For example, if full
meals were served on a flight from Chicago to
Indianapolis, that would be exciting. If not, customers
would hardly complain.
Kano’s Paired Questions
Ask the customer to consider a set of paired questions.
1. The first question asks how you feel if something exists.
2. The second question asks how you feel if something does
not exist.
Example:
Use 1-5 to answer:
1.
I really like it
2.
I like it
3.
I feel neutral
4.
I do not like it
5.
I really do not like it
1. How do you feel if the instructor has a good sense of
humor? (answer: ex. 1)
2. How do you feel if the instructor presents much useful
information? (answer: ex. 3)
Example:
Use A-E to answer:
A. I really like it
B. I like it
C. I feel neutral
D. I do not like it
E. I really do not like it
3. How do you feel if the instructor does not have a good
sense of humor? (answer: ex. C)
4. How do you feel if the instructor does not present much
useful information? (answer: ex. E)
Example: (con’t)
The first and third questions are paired and evaluate
instructor humor. They are useful in identifying humor as
an excitement or performance need.
The second and fourth questions are also paired evaluating
useful information given by the instructor. These questions
allow you to identify information as a basic or
performance need.
Step 3: Prioritizing the Requirements A weighting factor is generated for each requirement. The
weighting factor will give the designer an idea of how much
effort, time, and money to invest in achieving each
requirement.
Two questions should be addressed in developing a
prioritization
(1) To whom is the requirement important?
(2) How is a measure of importance developed for this
diverse group of requirements?
Step 4: Competition Benchmarking
The goal here is to determine how the customer perceives the
competition’s ability to meet each of the requirements. This
forces awareness of what already exists and points out
opportunities for improving upon that which already exists.
Each competing product is compared with customer
requirements. Some comparisons are objective and others are
subjective.
Below is a possible scale for rating the competition’s
product based on customer requirements.
1 = the design does not meet the requirement at all
2 = the design meets the requirement slightly
3 = the design meets the requirement somewhat
4 = the design meets the requirement mostly
5 = the design meets the requirement completely
Step 5: Translating the Customer Requirements
into Measurable Engineering Requirements
The goal here is to develop a set of engineering
requirements (often called design specifications) that are
measurable for use in evaluating the proposed designs.
1. Transform the customer requirements into engineering
requirements.
2. Make sure that the engineering requirements are
measurable.
Step 6: Setting Engineering Targets for Design
The last step is to determine the target values for engineering
measurement. To do this:
1. Ascertain how the competition meets the engineering targets,
2. Establish a target value for the new product.
Measurements of the competition’s targets provide a basis for the
development of targets for the new product.
• The best targets are those set for a specific value.
• Less precise, but still usable, are those targets set within a range.
• A third type of target is a value made to be as large or small as
possible.
House Of Quality
The House of Quality is a popular collection of several
deployment hierarchies and tables. It has the form of a table
that connects dots between the “Voice of the Customer” and the
“Voice of the Engineer.”
The House of Quality is used by multidisciplinary teams to
translate a set of customer requirements, using market research
and benchmarking data, into an appropriate number of
prioritized engineering targets to be met by a new product
design.
House Of Quality
•The House of Quality is a sort of conceptual map, which provides
means to the interfunctional planning and coordination of product
improvement and product development. In a way this method brings
the customer needs in the focus to design or to redesign the product
and service.
• In this method the starting point would be the customer needs which
are found from any market research survey about the product in
question. Primary, secondary and tertiary customer attributes are
found. These form the base of the house.
•Corresponding engineering characteristics are specified which should
be in clear measurable terms.
House Of Quality
•Now the interdependencies are mapped which are in the form
of the roof of the house.
•Accordingly, technical difficulties in achieving the desired
changes are calculated.
•With the help of imputed importance of each characteristic
the cost is worked out.
•Then final targets are set in clear measurable terms.
In essence, with the help of customer needs, the product is redesigned
in clear unequivocal measurable terms.
House Of
Quality
Correlation
Matrix
Product
Characteristics
HOW
Customer
Requirements
WHAT
Relationship
matrix
Marketing
Competitive
assessment
How Much
Engineering Competitive Assessment
The House of Quality contains six major
components:
1. Customer requirements (HOW`s). A structured list of
requirements derived from customer statements.
2. Technical requirements (WHAT`s). A structured set of
relevant and measurable product characteristics.
3. Planning matrix. Illustrates customer perceptions observed
in market surveys. Includes relative importance of customer
requirements, and company and competitor performance in
meeting these requirements.
The House of Quality contains six major
components:
4. Interrelationship matrix. Illustrates the QFD team's
perceptions of interrelationships between technical and customer
requirements. An appropriate scale is applied, which is illustrated
by using symbols or figures. To fill this portion of the matrix
involves discussions and to build consensus within the team,
which can be time consuming. Concentrating on key
relationships and minimizing the numbers of requirements are
useful techniques to reduce the demands on resources.
5. Technical correlation (Roof) matrix. Used to identify where
technical requirements support or impede each other in the
product design. Can highlight innovation opportunities.
The House of Quality contains six major
components:
6. Technical priorities, benchmarks and target are used to
record:
•The priorities assigned to technical requirements by the
matrix.
•Measures of technical performance achieved by
competitive products.
•The degree of difficulty involved in developing each
requirement.
The final output of the matrix is a set of target values for each
technical requirement to be met by the new design, which are linked
back to the demands of the customer.
House Of
Quality
Correlation
Matrix
Product
Characteristics
HOW
Customer
Requirements
WHAT
Relationship
matrix
Marketing
Competitive
assessment
How Much
Engineering Competitive Assessment
The “What” room

Implies the voice of the customer, located at
the left portion of the matrix.

It answers the question, “What requirements
should be satisfied, or are there any special
features which the customer would be
delighted to discover?”
The “How” room




Voice of the Engineers or Designers (“hows”).
Each "whats" item must be converted (refined) to
“how(s)”
They have to be actionable (quantifiable or
measurable)
It is located under the “Correlation Matrix” roof.
It answers the question, “How can these customer
requirements be met in terms of design
requirements?”
The “Relationship Matrix”




It is the linkage between the engineering design
requirements and voice of the customer.
Correlates how “hows” satisfy “whats”
Use symbolic notation for depicting weak,
medium, and strong relationships
Generally,
– A circle within a circle indicates a strong
correlation between the two.
– A single circle shows a moderate correlation
– A triangle represents a weak correlation.
The “How Much” room


“How much’s" of the “Hows“ (measurement)
Answers a common design question: "How much
is good enough (to satisfy the customer)?“

located in the box beneath the relationship
matrix.

Clearly stated in a measurable way as to how
customer requirements are met
Provides designers with specific technical
guidance

The “Correlation Matrix” roof




Identifies how “hows” items support (positive) or conflict
(negative) with one another
Find trade-offs for negative items by adjusting “how
much” values.
Trade-offs must be resolved or customer requirements
won’t be fully satisfied.
There are two consequences of a negative correlation.
– The first consequence is to redesign the product in order to
eliminate the tradeoffs.
– The second consequence is to determine an optimization target in
which the design tradeoffs are included with their relative
importance to the customer considered.
The “Engineering Competitive
Assessment” room

collects the data in engineering terms and
records it on the chart. Each item is scaled
separately as it relates to its relative merit
for each test from good to poor. The
“Engineering Competitive Assessment”
room is recorded below the “How Much”
room and corresponds to the “How” room
column. An importance rating is assigned to
each test on a certain scale.
The “Marketing Competitive
Assessment” room
Also called the “Customer Competitive
Assessment” room. Its location is next to
the “Relationship Matrix” room.
 This competitive benchmarking helps
identify the current best-in-class designs as
well as the strengths and weaknesses of
each design. A weighted scale is also
applied to the system.

An Example with
Completed QFD
Matrices:
Product Planning
Matrix for Pencil
BEFORE AND AFTER QFD
BEFORE
QFD
AFTER
QFD
PLANNING
DESIGN
PLANNING
REDESIGN
DESIGN
REDESIGN
MANUFACTURING
MANUFACTURING
BENEFITS
KEY DIFFERENCES
Before QFD
sequential development
function involvement by phase
management approval by phase
tasks assigned by function
functionally led decisions
presentation meetings
customer needs not integrated
After QFD
simultaneous development across functions
all functions participate from start
team empowered to make decisions
tasks shared across functions
consensus decisions about trade-offs
working meetings to develop results jointly
focus on customer needs carried throughout
Development time
$$
Customer satisfaction
To Build House of Quality
 Identify
customer wants
 Identify how the good/service will
satisfy customer wants.
 Relate the customer’s wants to the
product’s hows.
 Develop importance ratings
 Evaluate competing ideas and concepts
Ultimately you choose the design
Not the customer!
House of Quality Example
You’ve been assigned
temporarily to a QFD
team. The goal of the
team is to develop a
new camera design.
Build a House of
Quality.
© 1984-1994 T/Maker Co.
House of Quality Example
What the customer desires
(‘wall’)
Customer Customer
Requirements Importance
Light weight
Easy to use
Reliable
Target Values
House of Quality Example
Average customer
importance rating
Customer
Requirements
Light weight
Easy to use
Reliable
Target Values
Customer
Importance
50
30
20
House of Quality Example
Choose engineering
characteristics to satisfy the
customer requirements
Customer
Requirements
Light weight
Easy to use
Reliable
Target Values
Customer
Importance
50
30
20
Aluminum
Parts
Steel
Parts
Auto
Focus
Auto
Exposure
House of Quality Example
Relationship between
customer attributes &
engineering characteristics
(‘rooms’)
Customer
Requirements
Light weight
Easy to use
Reliable
Target Values
Customer
Importance
50
30
20
Aluminum
Parts
Steel
Parts
5
2
4
330
8
260
Auto
Focus
8
5
340
Auto
Exposure
7
3
270
Good Luck
with your designs!