Customer Effort Score (CES)
Customer Effort Score (short: CES) is a metric used to measure customer satisfaction with one single question. Instead of asking a customer if he or she is satisfied, the question is about the user experience. The underlying thought is that organisations create loyal customers by reducing customer effort.
There's evidence that in some cases the ease of a given experience is a better indicator of customer loyalty than simply measuring direct customer satisfaction. That's why the Customer Effort Score is a popular methodology employed by organizations everywhere. Instead of asking how satisfied the customer was, you ask them to evaluate the ease of their experience.
The Customer Effort Score can also be used to measure the aggregate experience someone has with a brand, but because the question implies a discrete and isolated user experience, it is most often used to measure service or product level issues. Most Customer Effort Score surveys are sent immediately after a customer service touchpoint (such as after an email support ticket has been resolved).