How to Use the Kano Model to Solve Problems

One popular framework that is sometimes taught for aspiring problem solvers is Design for Six Sigma. Design for Six Sigma is a unique application of Six Sigma tools and a unique framework where practitioners create and validate new designs rather than improve existing process designs. But it also balances the rigorous analysis of six sigma with many other ideas and techniques derived from human centered design (HCD) and design thinking. If you’ve ever taken a Design for Six Sigma (DFSS) course, then you’ve been introduced to the Kano Model, one of the most powerful conceptual frameworks in the DFSS curriculum. But even if you haven’t, the Kano Model is an incredible tool for understanding how different characteristics of a product, process of service deliver values in disparate ways. The Kano Model, developed by Noriaki Kano in 1984, provides a way of understanding and visualizing how unique product attributes satisfy customer wants, needs and desires differently. In particular, the model establishes and categorizes the relationships between product performance and customer satisfaction. And decidedly, no DFSS course is complete without it. But more and more, when introducing the model, many DFSS courses focus merely on the ideas and theory behind the model rather than actual implementation or execution of the Kano Model in industry. As a result, many DFSS-trained black belts are ill-equipped to put the model into practice. The whole DFSS module on the Kano Model becomes nothing more than a theoretical talking point. It becomes non-value added. We all hate waste, don’t we? Here briefly, I hope to give a primer on the real life deployment of the Kano Model, first by providing a summary of the model, and then by extrapolating on the requisite methods needed to truly put it to use.

The Kano Model and Diagram

The Kano Model and accompanying diagram represent a relationship between product performance and customer satisfaction. Product features and attributes are plotted on the 2-2 matrix which creates a landscape for understanding the relationship between the Y axis (Customer Satisfaction) and the X axis (Product performance). Just like a coordinate plane, the higher up on the Y axis, the greater the customer satisfaction and the further to the right on the X axis, the greater the product performance. Once plotted, all of the product attributes fall into one of three broad areas as demonstrated in Figure 1:

Figure 1: The Key Elements of the Kano Model

The definition of each is given below.

Delighters – These are product attributes that delight the customer simply by their inclusion in the product. They are the proverbial bells and whistles. A vehicle that can assist in parking, even though it might not execute this feature flawlessly or autonomously is nevertheless a delightful feature to an automobile. The same can be said for other semi-automation feature in automobiles like break assist and lane assist. Notice that they fall in an area of the figure where the customer satisfaction does not vary greatly depending on the performance of these attributes. They delight and thrill customers merely by being introduced into the product.

Dis-satisfiers – These are product attributes that a customer expects no matter what. There as what I refer to as “table stakes”. Anything but top notch performance of these attributes will dissatisfy a customer. The ignition system in a car must start every time. An ignition system that works most of the time will not cut it. A tire must hold air. A new computer must connect to the internet. A cell phone is expected to connect to the network and maintain a connection at the customer’s whim, at any time day or night. Even the smallest suboptimal performance will result in thoroughly dissatisfied end users.

Performance Attributes – In between these two domains is the area of performance attributes. When it comes to performance attributes more is better. More horsepower is better than less horsepower. Better fuel efficiency, lower cost, higher safety ratings. The Kano Diagram reflects these characteristic relationships in the direct, positive relationship between Performance and customer satisfaction. The greater the performance, the greater the customer satisfaction, and vice versa.

Finally, there is one important element to the model we have not yet discussed. Time. Time erodes and diminishes the relationship between performance and customer satisfaction. Automatic windows and FM radios were once only in luxury vehicles, but now most consumers wouldn’t dream of buying a car without these two primitive features. Mobile phone service providers used to tout “the fewest dropped calls” indicating a performance relationship between customer satisfaction and spotty network coverage. Now cell phone users will no longer tolerate any loss of coverage. The Arrow of Time on the diagram demonstrates the inevitable tendency for product features that once delighted us will eventually drift into mere product expectations.

The Value of the Kano Model is not to understand and explain why I can’t find a car with manual windows but rather to inform product developers, designers, and innovators of the fundamental forces and tendencies of how products create and deliver value to end users.  The Kano Model makes a visual representation of this reality and creates a taxonomy of what your product or service must have, how it needs to perform, and what it might include to delight the customer and set the product apart from the competition.

In many cases, this is where the Kano conversation stops. It is merely a conceptual framework for understanding how products and services deliver value to customers. But the Kano Model can also be surprisingly practical and prescriptive. All we need is some real market data. But in order to obtain these data, we must deploy a special, Kano-styled market survey. Afterwards, we can analyze the responses and map the results onto the Kano Diagram and framework. 

The Kano Survey

Most market research is designed to extract information about the customer. Customer sensitivity to price, aesthetic preferences, geographic information, demographic information, even psychographic information are all within the purview of contemporary market research. These are all well and good, but for all they do to help us understand the customer themselves, they tell us very little about the wants and desires of the customer in relation to the product itself. To this end, the Kano Survey is different. The Kano Survey is structured in such a particular way that it can extract these key customer-product data. More, the analysis of the Kano Survey responses is already predefined and standardized, making the interpretation of the results quicker to tabulate, easier to understand, and prescriptive to act upon.

 The most important part of the survey are the questions and prompts themselves. We call the prompts statement pairs. For each topic under investigation, the Kano survey prompts the respondent to respond to two similar statements. One statement will highlight a product feature with positive functionality of a particular product attribute, while the second statement highlights the same feature, but in a dysfunctional light. As an example, take a survey question from a real Kano Survey to develop a new consumer carpet cleaner:

Question 1 [Functional]: The carpet cleaner is easy to maneuver.

Question 2 [Dysfunctional]: The carpet cleaner is not easily maneuverable.

Here both statements seek to understand how the customer feels about one of the carpet cleaner’s attributes, namely, its maneuverability.  In the first statement, the customer reacts to a carpet cleaner that is easily maneuverable. In the second, the customer reacts to a carpet cleaner that is not. By formulating paired questions, the market-survey allows us to seek out a deeper understanding of customer product expectations. In the analysis phase, we will look for congruence between these responses and code them accordingly.

In addition to the statement pair prompts, the responses are also standardized on a 5-point Likert scale. For every statement the respondent is reacting to, they will be select one of five multiple choice options: (Like, Expect, Don’t Care, Tolerate, and Dislike).

The final phase of the Kano Survey is to analyze the results. To do this, we use a standardized logic matrix to harmonize the responses of the statement pairs:

Figure 2: Survey Response Logic Matrix

Where:

Q: Questionable – The response pairs were incongruent with one another.

P: Performance Attribute – The customer identifies this as a performance attribute.

I: Indifferent – The customer is indifferent to this attribute.

M: Must-Have – The customer expects this as part of the product.

R: Reversal – The functionality of the product is the exact opposite of what was expected. (To the customer dysfunction = function).

A: Attractive – These attributes delight the customer

Coding the Survey

From our carpet cleaner example, if Question 1 was answered as “Like” and Question 2 was answered with “Expect it” we would identify an attractive product attribute that would delight the customer. The logic makes sense. We have identified that the prospective end user expects a poorly maneuverable carpet cleaner and responds positively to a carpet cleaner that is easily maneuverable. The rest of the logic matrix is relatively straightforward. Response pairs that get coded as questionable would be generated when a respondent likes (or dislikes) both the dysfunctional and functional prompts. Performance characteristics are coded when the respondent likes the functional and dislikes the dysfunctional prompts. Must-haves are generated when the respondent is indifferent towards the functional prompt, but responds negatively to the dysfunctional prompt. Perhaps, what’s most interesting are the reversals. In these instances, the respondent acts completely differently than we anticipated (they prefer the dysfunction).

By making sense of the logic and coding, product developers and market analysts can find unique insights and deep understanding in customer expectations and product features.

It's also likely that not all the respondents in the survey will agree. Some may seem indifferent to the product attribute in question, others may expect it and still others might think of the product attributes as performance metrics. Whatever the case, you’ll need to reconcile the disparate survey responses and prioritize the results. The simplest and most straightforward way of doing this is to tally each rating for a statement pair and then assigns the dominant rating, which is the most frequent rating, as the result of that particular statement pair. So for instance, if five respondents responded to a statement pair and their results were:

Indifferent = 3

Attractive = 2

Then we would code this particular product attribute as one where the customer is indifferent to the product feature in question. It may not be ideal, but in balancing the constraints of time, transparency, and understanding, it’s a defensible methodological choice that keeps the project moving forward. Finally, though it’s not required, you can map the responses to the Kano Survey onto the Kano Diagram.

Figure 3: Carpet Cleaner Attributes Mapped to Kano Diagram

Who is responsible for deploying the Kano Model?

When it comes to personnel management, the Kano Model is no different from other Lean and Six Sigma (LSS) endeavors. The best practice is to involve a cross-functional team that represents key stakeholders from different affected areas of the business. While the list is not exhaustive, a good Kano cross-functional team should include individuals from marketing, sales, product development, and operations. Each of these functions can bring their unique experiences and expertise to the team. Moreover, together, they can acquire market-based insights about potential product opportunities that can be taken back to their functions and become the basis for further functional development, growth and learning. Each of these functional representatives should be involved in all parts of the product development process. From the initial concept through taking the product to market through sales and promotion.

Conclusion

The Kano Model is an excellent tool for understanding customer satisfaction amid product performance and attributes with wide applications beyond Lean and Six Sigma. Unfortunately, the Kano Model is not widely known and used. It is rarely presented to marketing or product development, and even when presented in a DFSS context, it is often presented incompletely. The survey methodology outlined here is the missing link to Kano theory and the useful deployment of the model and tool. Moreover, by demonstrating the practical application and deployment of the Kano Model the Lean and Six Sigma community can make progress in moving this invaluable tool from the shadows and into the mainstream of marketing and product development.

This article, originally appeared in the November 2022 issue of The Lean Six Sigma Review. Michael remains its sole author.