Why is the customer always right

A business' main aim is to keep the customers happy and satisfied since the business' prosperity depends on getting loyal customers. 

Assuming that the customer is always right saves the business the trouble of the customer making a big scene and possibly tarnishing the business' reputation.

Dealing with customers on the basis that they're always right is considered good business ethics since it shows that the business is built on the grounds of faithfulness and dedication.

Customer service divisions deal with the fact that the customer is always right in order to gain the customer's trust and loyalty and ensure that they stay affiliated with the business.

In order to win the customer's loyalty, the business has to make sure that the customer isn't frustrated or angry with their service.

Many businesses think that customers are out to cheat and manipulate them, while in fact customers are humans just like the business' owner and employees and usually don't have bad intentions.

Providing excellent customer service and keeping the customer satisfied make the customer invite their friends to try out the business' service, which increases the business' success. 

The belief that the customer is always right makes customer service employees more tolerant, patient and calm when dealing with unsatisfied customers. This enhances their communication and customer service skills.