Customer needs are what the customer requires from your service. The thing that they intend to get from it. Customer expectations are how they hope the service/ quality will be like and the customer satisfaction is achieved when both of these are met and the customer is happy. All of these are closely related. If the business doesn’t serve the needs of a customer then the expectations of the company set by said customer isn’t met which then means that the customer leaves unsatisfied. If a business meets the needs of the customer but the quality of the service isn’t as they expected then, again, the customer isn’t completely satisfied. However, when both needs and expectations are fully met and an all-round good service has been provided then you are left with a customer who is satisfied and is likely to use your service again.