Customers “pay the bills,” so it’s important to understand their needs. Customers behavior as key input to strategy and process design. Value driver “levers” are pulled by an external customer. They define the “playing field”. Serve as referee for all competitors. Define “value-added” activity or service. They are always right, even if we cannot meet their needs, or do so profitably.

Who are the customers? Any person or organization that receives a product or service (Output) from the work activities. Those whose needs must be met for a process to be successful? They are external customer outside of your business; usually payers for your products and services. They are internal colleagues who receive products, services, support or information from your process. They are regulators such as a government agency with required process standards. 
What is the “Voice of the Customer”? Voice of the Customer (VOC) is the expression of customer needs and desires. The VOC can be compared to internal data (“Voice of the Process”) for assessing current process performance or process capability.

Why do we need to collect the Voice of the Customer? The VOC is an affirmation that an issue exists. It also is a direction towards which to investigate a root cause. It is guidance towards developing a Null Hypothesis and desired outcome. In short, the VOC is an indication that a process has room for improved efficiency.

The VOC is a critical component of the Lean Six Sigma DMAIC process when developing a project around resolving an issue. The VOC also has bearing on application rationalization, strategic roadmaps and should be collected on a regular basis to keep an IT Department in tune with its environment.