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How Critical is Quality: the Critical to Quality Tree

published on September 12, 2011

As I cover some of the methods used in to measure quality in Six Sigma, I wanted to hit on determining what defines quality and apply to a usable example. The method I want to talk about today is the Critical to Quality Tree (QTC). QTC is tool that helps the organization determine what is critical to its success. There are four basic steps in creating a QTC:

Identify the customer

This may not seem like rocket science but it is actually the most missed guess of businesses. When I say identify the customer, I mean take a step back and really look at who buys your products or services. The most commons buyers are your customer base, they may not be who you want but they are the most frequent users so build your products and services around their needs.

Identify the customer’s needs

What customers need and what they want are two very different things. In this step you have to identify what the customer needs to be satisfied.  For example if you are a cell phone manufacturer,your customer needs to have a product that at the very least allows them to place and receive calls.

Identify the 1st set of customer requirements.

The first set of requirements should be identified as basic/threshold attributes, these are products features that your customers will just assume to be present and if they’re not the customers will be dissatisfied. These features are the most important because they are the basic product requirements, think of them as the foundation of the house.

 Identify the 2nd set of customer requirements and try to take that to another level of specialty.

This set of requirements will occur in two areas: performance attributes and exciters/delighters. Performance attributes are features that are directly related to customer satisfaction. An example of this would be a 10 second or less hold time for customer service representatives. An exciter/delighter is a feature that delights the customer and leads to high satisfaction, but won’t affect satisfaction if it isn’t present. These are the requirements that create aesthetic value and are mostly present for a wow factor.

Once you have completed those four steps, you’re ready to move on to creating the tree. So, what does a Critical to Quality Tree Look Like? An example of the CTQ is below.

chart on the critical to quality tree


This example is a way to help your organization began the conversation of what the customer’s values and how the organization can create processes that nurture that value. This is not a step by step guide, but it should be able to help you begin to lay the foundation.

published on September 12, 2011


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