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Harish Jose


A ‘Complex’ View of Quality

Customer-centric is more than a catchphrase

Published: Tuesday, October 2, 2018 - 12:03

I am a quality manager by profession. Thus, I think about quality a lot. How would one define “quality?” A simple view of quality is “conformance to requirements.” This simplistic view of quality lacks the complexity that it should have. It assumes that everything is static, the customer will always have the same requirements, and will be happy if the specifications/requirements are met.

However, customer satisfaction is a complex thing. Customers are external to the plant that manufactures the widget. Thus, the plant will always lack the variety that the external world will impose on it. For example, let’s look at a simple thing like a cell phone. Theoretically, the purpose of a cell phone used to be to allow the end user to make a phone call. Think of all the variety of requirements that the end user has for a cell phone these days—internet, camera, ability to play games, ability to use productivity apps, stopwatch, alarms, affordability. Additionally, the competition is always coming out with a newer, faster, and maybe cheaper cell phone. To paraphrase the Red Queen from Alice in Wonderland—the manufacturer has to do a lot of running to stay in the same place—to maintain the share of market.

In this line of thinking, quality can be viewed as matching the complexity imposed by the consumer. There are two approaches in quality that differ from the concept of just meeting the requirements.

Taguchi’s idea of quality

Genichi Taguchi, a Japanese engineer and statistician, came up with the idea of a “loss function.” The main idea behind this is that any time a product deviates from the target specification, the customer experiences a loss function. Every product dimensional specification has a tolerance for manufacturability. When all of the dimensions are near the target specification, the loss function is minimal, resulting in a better customer experience.

One of the best examples to explain this is from Sony. The story goes that Sony had two television manufacturing facilities, one in Japan and one in the United States. Both facilities used the same design specifications for television. Interestingly, the televisions manufactured in the U.S. facility had a lower satisfaction rating than the televisions manufactured in Japan. It was later found that the difference was in how the two facilities approached quality for the color density. The paradigm that the U.S. facility had was that as long as the color density was within the range, the product was acceptable; whereas the Japanese facility made a point to meet the nominal value for the color density. Thus, the Japanese Sony televisions were deemed superior to the American Sony televisions.

Kano’s idea of quality

Noriaki Kano is another Japanese quality management pioneer, who came up with the idea of the Kano model. It’s a great way of looking at a characteristic from the point of the customer. The Kano model has two axes—customer satisfaction and feature implementation. The customer satisfaction goes from satisfied to dissatisfied, and the feature implementation goes from insufficient to sufficient. This two-dimensional arrangement leads to various categories of “quality,” such as attractive quality, one-dimensional quality, must-be quality, and indifferent quality. Although there are more categories identified by Kano, I am looking only at these four.

Attractive quality
This is something the customer would find attractive if it is present, and indifferent if it is absent. For example, let’s say that you went to get a car wash, and the store gave you a free beverage and snack. You were not expecting this, and getting the free beverage and snack made the experience pleasant. If you were not aware of the free beverage and snack, you would not be dissatisfied because you were not expecting to get the free beverage and snack.

One-dimensional quality
This is something that a customer would view in a single dimension. If there is more of it, the customer is more happy, and if there is less of it, the customer is less happy. For example, let’s look at the speed of your internet connection at home. The faster the internet, the happier you are, and the slower the internet, the less satisfied you are.

Must-be quality
This is something that the customer views as an absolute must-have. If you go into a store to buy eggs, you expect the carton to have eggs in it. If the eggs are not there, you are not happy.

Indifferent quality
This is something that a particular customer truly does not care about. The example that Kano gives to explain this in his 2001 QMOD Conference paper, “Life Cycle and Creation of Attractive Quality,” was the “I-mode” feature on some Japanese cell phones. This feature allowed the user to connect to the internet. When a survey was conducted, most of the middle-aged people viewed this feature indifferently. They couldn’t care less that the cell phone could be used to connect to the internet.

The brilliant insight from the Kano model is that the perception of quality is not linear or static. It evolves with time. Kano hypothesizes that a successful quality element goes through a life cycle like the one detailed below:

Indifferent => Attractive => One-Dimensional => Must-Be

A feature that began as indifferent could become an attractive feature, which would then evolve into a one-dimensional feature, and finally it becomes a must-be feature. Take for example the ability to take pictures on your cell phone. This was treated indifferently at the beginning, and then it became an attractive feature. The better the resolution of the pictures taken, the happier you became. Finally, the ability to take sharp pictures became a must-have on your cell phone.

The customer is not always aware of what the attractive feature could be on a product. This is akin to what Ford said: “If I had asked people what they wanted, they would have said faster horses.”

Steve Jobs added to this and said, “People don’t know what they want until you show it to them. That’s why I never rely on market research. Our task is to read things that are not yet on the page.”

Kano had a brilliant insight regarding this as well. In his 2001 paper, he gave the Konica model as an example. Kano talked about the camera that Konica came out with during the 1970s that had built-in flash and the capability to auto focus. At that time, the camera was treated as a mature product, and to survive the competition, Konica decided to come up with a new camera. Konica engaged in a large survey with customers, expecting to come out with a completely new camera as a result. The R&D team was disappointed with the survey results, which only suggested minor changes to the existing designs. The team decided to visit a photo processing lab to examine the prints and negative films taken by consumers, and to evaluate the quality of prints and developed films. This is the spirit of genchi genbutsu in lean (i.e., go and see to grasp the situation). The team learned that the two main issues the users had were to do with underexposures due to lack of flash and out-of-focus images.

Kano notes that:
“To solve these problems, Konica developed and released cameras with auto focus and a built-in flash as well as auto film loading and winding functions from the middle to the end of 1970s. This prompted consumers to buy a second and even a third camera. Thereafter, Konica’s business considerably grew and completely changed the history of camera development in the world.”

As long as customers are around, quality should be viewed as nonlinear, complex, and evolving.

Always keep on learning....

First published Sept. 8, 2018, on Harish’s Notebook.


About The Author

Harish Jose’s picture

Harish Jose

Harish Jose has more than seven years experience in the medical device field. He is a graduate of the University of Missouri-Rolla, where he obtained a master’s degree in manufacturing engineering and published two articles. Harish is an ASQ member with multiple ASQ certifications, including Quality Engineer, Six Sigma Black Belt, and Reliability Engineer. He is a subject-matter expert in lean, data science, database programming, and industrial experiments, and publishes frequently on his blog Harish’s Notebook.


Kano Categories

Thanks for the great article Harish - I like the very concise explenation of the Kano model.

One question: what's your opinion regarding the reverse and questionable category of the model? I know that there are some people who don't consider those two categories at all. I believe they are not part of the original model but were added later? Just wondering what your thoughts on this are :)