There are scores of books and numerous articles written on this subject by people with far more credentials than I possess; however, maybe we shouldn’t over think this conundrum which might allow us to come up with a fairly simple answer.
Some people have the mistaken idea that people with high self-esteem think that they are perfect. But the truth is that people with high self-esteem are always looking for ways they can improve.
Dealing with an unhappy customer doesn’t mean the customer is always right, but dealing with customer complaints presents frontline employees the chance to show your organization really cares about treating them with respect.