MONDAY, JULY 23, 2018
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Methodology VOC/Customer Focus Use Pair-wise Questioning to Collect More Useful VOC Data

Use Pair-wise Questioning to Collect More Useful VOC Data

Imagine receiving the following message from your organization’s travel assistant:

“You will really like your next business trip! I have booked you into a hotel right in the city center. It is a bit far from the factory and not really cheap, but after work you can do lots of things!”

But what if you would have preferred to stay at a quiet hotel by the seashore, just a 15-minute drive away from the factory, rather than in the bustling city center? If the travel assistant had collected the voice of the customer (VOC), you might have been more satisfied with the trip.

This example is a reminder of how important it is to gather VOC. Getting VOC right is highly important when designing a product or offering a service. The Kano model, along with “pair-wise” questioning – a method for testing the desirability of certain product or service parameters – can aid in this job. These analysis methods help practitioners to classify customers’ perceptions of service or product attributes, and to understand effects they can have on customer satisfaction. By using these tools, everyone will be closer to receiving the kind of services and responses that they want.

Understanding the Kano Model

The Kano model, shown in the figure below, distinguishes between three different types of attributes:

  • Delighters have little impact on customer satisfaction when absent, but they strongly increase it when present.
  • Basic attributes often only go noticed when they are absent. If they are missing, customer satisfaction can drop significantly.
  • Performance attributes can increase or decrease customer satisfaction, depending if they are present or not. Customer satisfaction grows along with the fulfillment of these attributes.

Kano Model

Kano Model

The business trip example can help to further explain the Kano model. For instance, besides being located reasonably close to their place of work, many travelers want to choose from a range of restaurants, cinemas, theatres or other leisure facilities once their work is done. Put simply: The more choice the better. Thus, the number of facilities within reach is a performance attribute. Nowadays, high-speed Internet access in a hotel has turned into a basic attribute. Business travelers expect to find it; thus, its presence does not positively impact satisfaction. However, if the web service is too slow, intermittent or absent, satisfaction can drop considerably.

Also, hotels sometimes charge excessively for national or even local phone calls. This clashes with the traveler’s home experience, where most have a flat rate for their national calls and cheap options for international calls. This context can make the price of a phone call from a hotel room a delighter attribute: At a low (or flat) rate, customers can call their family without worrying about the phone bill. Their satisfaction increases suddenly when the rate drops below a certain threshold. For prices above that threshold, they may use their cell phone. At that point, satisfaction will remain unaffected, no matter how high the rate really is.

Dealing with Different Attributes

Once practitioners are able to classify attributes under the delighter, performance or basic categories, they can take these attributes into account when designing a product or service. Each type of attribute must be addressed appropriately, which is why it is important to get the classification right.

For a basic attribute, like high-speed Internet access in a hotel room, a threshold needs to be established. This can be done by asking customers: “How do you use your Internet connection?” The hotel can then determine the bandwidth needed to support these habits. Typically, thresholds for basic requirements stay stable over time. It is advisable, though, to monitor related usage patterns and to also ask questions such as: “How would you like to use your Internet connection?” In the near future, business travelers may expect to watch their home TV stations via the Internet. Spotting such a trend early can lead to the offer of a delighter. This way, what now is a basic attribute (bandwidth) might become a delighter in a different context in the future.

With that said, a delighter attribute does not necessarily lead to a design feature, because the absence of a delighter often goes unnoticed. However, design teams should challenge all reasons why delighters can’t be built into a product or a service: “Why shouldn’t hotels be able to negotiate flat rates for their rooms with the local telephone company?” Taking such questions seriously is important for two reasons. First, delighter features can help organizations to avoid “buying” customer satisfaction through price abatements. Second, if the competition finds a cheap way to design the delighter or simply decides to offer it, the attribute can quickly turn into a basic requirement. If customers start getting used to being delighted this way, not offering this former-delighter-turned-basic-requirement can lead to a severe drop in customer satisfaction and, in the worst case, to the loss of customers.

Performance attributes can be used to increase customer satisfaction. Often, however, an increase in these attributes can lead to a higher product or service cost. Design teams should challenge this link between performance and cost: “How can I give my business travelers more of the options they want without booking them into expensive hotels?”

Analyzing Customer Data

Design teams may struggle with how to categorize attributes as delighter, performance or basic appropriately. Especially in the absence of an experienced facilitator, the Kano analysis can be an exercise team members are reluctant to participate in.

Such teams then fail to use their best knowledge to understand VOC and design the right features into a product or service. Tracing back the nature of an attribute to the original VOC can be difficult. When interviewing customers, practitioners cannot simply ask questions like, “Are you delighted by…?” Consequently, teams often guess or vote for the nature of an attribute. This can make the outcome unsatisfactory and also reduce team members’ appreciation of Kano analysis. As a result, insufficient care may be taken in designing features of a product or service that addresses these attributes.

Introducing Pair-wise Questioning

To ease the Kano analysis process, teams can use pair-wise questioning to determine the nature of an attribute. Pair-wise questioning, which can be applied in customer interviews and questionnaires, allows for a rational and consistent classification of attributes.

Consider the situation of a supplier to the shipbuilding industry. This medium-sized company is reviewing its portfolio for air-conditioning equipment and related services. The engineering team considers the following attributes to be important to shipbuilding customers:

  • Instructions for operation, including contact information for the supplier’s engineering department if issues arise
  • The time it takes to have a knowledgeable contact person on the ship construction site
  • The noise level of the air-conditioning equipment
  • The fit of any specific equipment into a wide range of environments

The team wants to understand the nature of these attributes better. They use pair-wise questioning to determine the customer perspective. They ask customers the following questions regarding each of the four attributes:

  • “How do you feel if the attribute exists?”
  • “How do you feel if the attribute does not exist?”

For each of these questions, the possible answers are:

  • “I really like it” (++)
  • “I like it” (+)
  • “I feel neutral about it” (o)
  • “I don’t like it” (-)
  • “I really don’t like it” (–)

The team used the classification system in Table 1 to interpret the nature of the attributes.

Table 1: Classification of Attributes Using Pair-wise Questioning
 How do you feel if the attribute exists?
How do you feel if the attribute does not exist?++InconsistentIndifferentNegative exciterNegative exciterNegative performance
+IndifferentInconsistentIndifferentIndifferentNegative basic
0Positive exciterIndifferentInconsistentIndifferentNegative basic
Positive exciterIndifferentIndifferentInconsistentIndifferent

Classification Options

As seen in Table 1, inconsistency may arise if the pair-wise questions being asked are not suited to classify the attribute appropriately (a problem of the measurement system). In this case, further follow-up with the customer will be needed.

Attributes classified as “indifferent” in Table 1 may be added as features, just to be safe, if they are not too expensive. Before doing so, however, teams should consider the overall complexity of the resulting offer. Why dilute the essence of a product or service with features that customers are indifferent to? Further follow-up may also be needed regarding these attributes.

Table 1 also shows that there are not only “positive” but also “negative” performance attributes, where less is better. Often (though not in the above example for phone calls from hotel rooms), price may be a performance attribute.

Similar to “more or less is better” performance attributes, there are also positive and negative excitement attributes. These can make a real difference when present (for positive exciters) or absent (for negative ones). A positive exciter leaves customers indifferent when absent, while a negative exciter does so when present. The same distinction can also be made for basic requirements.

While it is important to know that positive and negative performance, exciter, and basic attributes exist, facilitators should not insist on working out a clear separation between them. Rather, the distinction should be made to clarify doubt about the right category. Practice with the Kano model will further help teams to make quick distinctions.

Asking the Questions

With this understanding of pair-wise questioning, the team from the air-conditioning equipment manufacturer produced pair-wise questions and, as a test run, answered them for themselves. While this is clearly not the VOC, the exercise revealed different perceptions among team members about customer preference. The team developed a sensitivity and curiosity about the customers’ original feedback, and also helped fine-tune the list of questions to be asked in the coming interviews.

The customer interviews were carefully prepared. Each of the interviewers had a well-defined role. The lead interviewer guided the conversation and asked the bulk of all questions. Two other team members had the role of spotting the answers to specific attribute present/attribute absent questions. They were also prepared to record the non-verbal part of the communication. In case the interviewers were not sure about the answer, or whenever the lead interviewer neglected to ask the appropriate question, the other team members in the room would pose an additional clarifying question. The roles of the team members were mixed so the interviewed customer was not always confronted by an attribute exists/does not exist-type question from the same person. Also, all interviewers were trained to ask their questions in a variety of ways to be able to adapt better to the flow of a discussion.

In the investigation, it turned out that most customers:

  • Like the idea of phone numbers to call for help listed on the air conditioner instructions, but feel neutral if the numbers are not present
  • Like having quick access to a knowledgeable representative of the supplier, and really don’t like situations when nobody is available
  • Really like quiet air conditioning systems and really don’t like noisy systems
  • Really like the equipment to fit into a wide range of environments, and remain mildly disappointed when it does not

The team then went on to analyze these results with the help of Table 1. The outcome is listed in Table 2.

Table 2: Analysis of Interview Results and Actions Taken
AttributeCustomer FeedbackType of AttributeDecision Taken
Phone number to call for help listed on instructions+ if present, 0 if absentIndifferentThe team will make sure the company footer, including contact information, is always complete and part of all official letters.
Quick access to a knowledgeable representative+ if present, — if absentBasicHaving a representative on site at all times is expensive. Thus, the team will create a hotline that will link to a mobile phone handed to the expert in charge, who will drive to the site, if needed, within four hours.The team also will track the reasons why this person is contacted and work to reduce the occurrence of problems.
Low noise level of air conditioning equipment++ if present, — if absentPerformanceThe team will have designers work with the customer to reach an acceptable noise level. In the long term, the team will find ways to transfer (expensive) military low-noise solutions to commercial ships.
Fit of equipment into many environments++ if present, – if absentExciterThe team will have designers work with customers to formulate common and lasting standards.

Taking the Next Steps

An organization can take the following steps to integrate Kano analysis and pair-wise questioning into their VOC collection and design processes:

1) Define the purpose of the VOC study: This may be something like: “We want to understand what customers value in our engineering and service offers. We also want to explore ways to deepen the collaboration with our customers to create valuable propositions for building quality merchant vessels and yachts.”

2) Select and train the team: The team should include members from the engineering, quality and sales departments. The team also should be trained in the Kano model, pair-wise questioning and asking these questions in different ways.

3) Identify the customers: The team must create a list of all customers currently served, and identify the decision makers at these organizations. Decision makers could range from heads of purchasing and engineering departments to long-serving experts and senior managers.

4) Prepare the interview: After brainstorming and discussion, members of the team should draft interview questions. These questions can then be answered by the team to demonstrate the diversity of customer perception inside the team and provide a chance to fine-tune the questions. Roles in the teams should be clearly distributed, down to individual questions.

5) Conduct the interview: Next, the team must schedule site visits with various customer representatives. Each interview should start with a five-minute briefing and end with a debriefing, so that team members can immediately collect and record impressions and non-verbal customer feedback from the interviews.

6) Analyze the results: Results from the interview can then be analyzed using the Kano model. The team should share the results, highlight any surprises in the feedback and conduct further discussions with the wider sales, engineering, quality and management teams.

7) Develop an action plan: The customer data may result in several quick-win improvement projects. It may also help to schedule regular meetings with customers on certain problem topics.

Part of the Flow

After a comprehensive VOC exercise, it is difficult to nail down the contribution of a single element, such as pair-wise questioning, to the overall success. While this method allows practitioners to determine the nature of an attribute directly from customer statements, using it inconsistently can considerably reduce its sharpness. To design the best products or services, teams must understand the process flow – from the planning and collection of VOC data to the definition and execution of an action plan.

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Leave a Comment



Great article; your points are clear and well made.

As an extension of this thinking we could take the customer desire; understand the solution they are looking for (actual solution, expected product function or service level) and build a specific experience around this customer.

Of course the business needs to focus on who it wants it customer to be – high/low end, child/teenage or adult/senior, male/female etc. focusing in helps the odds of hitting bull’s eye.

Testing & measuring then assists in the fine tuning raising the customer satisfaction [output] from fulfilment through to delighter.

There are multivariate reasons for the choices we make; designing the architecture for the desired customer through customer centric thinking can only go a long way to bridging the gap.

Great work, look forward to reading more of your material.


The concept is excellent, but this guy did not write it….someone who holds a doctorate should know to give credit where credit is due for the method.

You can read about it in more detail in the “Center for Quality of Management Journal” circa 1993

Michael Ohler

Thanks a lot indeed for the link provided by SixSigmaMBB!
Great and very clear material!

Of course, I have not invented the Kano concept, I have also not invented the pairwise questioning or a way to conduct such interviews. After 10000 years of document human history it is in fact difficult to come up with a genuinely new thought, also in Lean Six Sigma.

I think, though, what counts is exchanging experience in using (eventually old) concepts in today’s ever-changing business environments.
Having had your article at hand at the time of writing up the article, I may have been able to focus better on experience and less on explaining the underlying concepts.
Those who prefer reading things in one flow may foregive this waste of writing what has been written already.


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