Since Howard and Sheth (1969) applied the concept of satisfaction to the consumer theory, many scholars
also brought their opinions. Appendix 3 shows the definition and context of customer satisfaction. It can
be concluded from the definition of customer satisfaction that customers in a broad sense include internal
customers and external customers. Customer satisfaction should be preceded from the inside to the
outside. The mutual relations between internal customers and external customers are inseparable for
businesses to reach the goal of total customer satisfaction. While the company takes the needs of external
customers into consideration, it is necessary to manage the needs of internal customers as well. Customers
would feel satisfied if they feel the real performance equal to or better than prior expectations—otherwise
they would feel dissatisfied if the performance worse than prior expectations.