How would you define good customer service?

"I agree with the statement on the company website that good customer service exceeds the customer's expectations in both quality of service and the speed that the service is delivered. Recently, I had a customer who was unhappy and was trying to get a refund. I wanted to make sure that they left our store happy with the resolution I provided. So, I made sure that the customer's concern was taken care of quickly. I apologized to them for their dissatisfaction and gave them a small gift certificate in return for the bad experience."