The Kano model challenges the idea that improving every aspect of your product results in an increase of customer satisfaction. In reality, there are areas of basic expectation in a product that a customer would always expect to be there – often these can require a large amount of effort to develop. Conversely, there may be features that would impress users but require very little effort to create.

Categories of features

Basic features – must be present in order for users not to be dissatisfied.

Indifferent features – Features that don’t affect a customers’ satisfaction one way or the other.

Linear features – the more of these there are, the more satisfied a user is.

Delighters – Features that are high up the satisfaction scale.

We can’t create only features that are high in satisfaction. This is because of the Functionality dimension, which represents how well a feature has been implemented, how much has been completed or how much it cost to develop.

The Four categories of Features

Basic/Mandatory features
Features that users expect to exist in a product are unlikely to score highly on satisfaction, but developing them can be costly. But if a basic feature doesn’t exist, users are likely to complain.

For example, a basic feature for a hotel would be ensuring 24 hour hot water. They require large expensive boilers (with associated fuel usage) that can supply instant hot water. The hotel must spend huge amounts on ensuring the hot water is available, but users will never get excited by it because it’s something they expect.

Indifferent features
Features that don’t really affect the satisfaction level of users. So no matter how much effort is put into developing them, it won’t make any difference to the happiness of your users. Because of this, think carefully about if you should be developing these features.

Linear features
The more you provide, the more satisfied users become. For example, battery life of a mobile device.

Delightful features
These are features that score highly on satisfaction, but may only take a small effort to create. If they aren’t present, a user is unlikely to complain. But if they are present, they will be delighted by the product.

Going back to the hotel example, providing guests with a free drink probably only costs a few pence, but is likely to score highly on satisfaction.

Delight changes to Basic

Over time, features that were originally classed as Delighters, will change to Basic features. For example, once users start to expect a free drink on arrival at their hotel, they will become dissatisfied if they were to no longer get the drink – it has become a basic feature.

Using the Kano Model to prioritise the Product Backlog

To discover how users see our products’ features, we conduct a Kano questionnaire. For each feature, we ask two questions:

• Functional – How do you feel if this feature is present?
• Dysfunctional – How do you feel is this feature is absent?

For each question, the user may answer with one of the following:

• I like it
• I expect it
• I am neutral
• I can tolerate it
• I dislike it

Their answers can then be categorised using the following grid:

Mandatory
Linear
Exciter
Questionable
Reverse
Indifferent

So if a user answers the functional question with “Like” and the dysfunctional with “Neutral”, the feature will be classed as E, or Exciter.

You’ll notice we also have two new categories:

Questionable – these occur when the user gives conflicting answers e.g. like for both answers. This suggests there’s something wrong with what you’re asking.

Reverse – this suggests the user actually wants the opposite of what we’re suggesting for the feature.

Once your users have completed the questionnaire, you can aggregate the results. For each feature, add up the responses in each Kano category. The category for a particular feature is the one with the largest amount:

So we can see that login using Facebook is a Mandatory feature, upload a photo is Linear, and share photo with friends is an Exciter.

When it comes to prioritising the Product Backlog, you need to include the Mandatory items as your highest priority, followed by Linear and then Exciter.

Duncan Halley is a certified Scrum Master (PSM I). You can read his blog here.

Follow him on Twitter: @duncanhalley