Voice of the customer - VOC

Customer satisfaction is the starting point for Six sigma. If we satisfy the customer he will be buying our products or services again and generating more revenue in the future. In order to implement this customer-focused approach, we need to understand what the customer really wants. Six sigma refers to this as the voice of the customer or in short VOC. The Voice of the Customer captures the customer’s feedback about their experiences with and expectations for your products or services. It captures what they like and what they do not like. In the end, it will let you produce a list of customer wants and needs.

What the customer wants and needs, in other words the customer requirements, are also called Critical-to-Quality (CTQ) requirements. With these CTQ requirements, which are derived from the voice of the customer, we can develop our products or create our services. If the CTQ requirements are met we can match or even exceed the customer expectation. In other words, if we capture the voice of the customer correctly, we will be able to improve the quality or value of our product or service.

Who is the customer

First of all, we need to understand who our customer is. The first distinction we can make is the distinction between an external customer or an internal customer. An external customer is somebody from outside of your organization. While an internal customer is somebody within your organization who receives the output of your work. This is often the next step within the process.

We can distinguish external customers further. You have the direct ones who receive the goods or services offered by your business. But you also have a secondary and tertiary customer. Those are customers who receive our products or services through another party. Finally, you can have indirect customers. Those are customers who do not receive or pay for the outcome of your process but have a vested interest in what you do. The government is a typical example of an indirect customer.

If we know who our customers are we can move on to capturing the voice of the customer. Capturing the voice of the customer is key. Only if we really know what the customer wants, we will be able to fully understand what we need to improve.

Capturing the Voice of the Customer and translating it into requirements

There are many methods to captures the voice of the customer such as Personal Visits, Interviews, Conferences, Customer Complaints, .... You have to take into account that the Effectiveness of data gathering increases when the closeness to the customer increase.

Once we have gathered the voice of the customer we need to translate these into clear requirements. Imagine the following scenario. A restaurant holds a survey with his customer. They find out that customer is not happy that they have to wait so long for their food. In other words, the voice of the customer states that the waiting time is too long.

Now we know what we need to improve, but we need to translate this voice of the customer is a requirement we van measure. We could specify the waiting time as the time between the order is taking at the table and the time we serve the food at the table. Another possibility is that we take the time between the customers are entering the restaurant and the time we serve the food at the table.

We need to understand really what the customer needs before we create an operating definition for the requirement. Once we agree on the operating definition we have to agree on the target. What is too long, is it 15 minutes, 30 minutes or even more.

As you can see even it is not that easy to capture the voice of the customer and translate it into requirements. Once you have defined your operating definition and target, do not forget to verify it with the customer to see if this is really what he wants.

Changing requirements

Be aware that the world around us is constantly changing. this means also that what the customer needs today, he maybe does not want tomorrow. Do you want to buy a phone today which has been designed 5 years ago? Probably not!. Therefore you need to constantly renew the voice of the customer. Because in the end, the customer decides what is the value or quality of the products and services that you are offering.  

This article was updated on November 30, 2022