A key way to understand how well a company serves its customers is to look at the effort it takes customers to communicate with the company. Suhm presents the Caller Effort Index (CEI), a cross-industry benchmark that’s based on automated measurement of many dimensions of customer effort and correlated with callers expressing frustration during the call. Ball presents the concept of Customer Effort scores as an attempt to quantify the amount of work it takes for customers to work with a company.