According to the website, iSixSigma, The “voice of the customer” is a process used to capture the requirements/feedback from the customer (internal or external) to provide the customers with the best in class service/product quality. This process is all about being proactive and constantly innovative to capture the changing requirements of the customers with time. The “voice of the customer” is the term used to describe the stated and unstated needs or requirements of the customer. The voice of the customer can be captured in a variety of ways: Direct discussion or interviews, surveys, focus groups, customer specifications, observation, warranty data, field reports, complaint logs, etc. This data is used to identify the quality attributes needed for a supplied component or material to incorporate in the process or product.
http://cerasis.com/2013/08/16/voice-of-the-customer/
Is the customer always right? Maybe not, but their thoughts will always be an integral part of improving customer experiences. The Voice of the Customer (VoC) refers to feedback from customers on “their experiences with and expectations for your products or services”, according to survey software company Qualtrics. Feedback is more than just a survey—collecting VoC data is an in-depth process that compiles detailed information that companies can use to improve processes successfully.
https://blog.salemove.com/what-is-voice-of-the-customer-and-why-does-it-matter/