How do you define ? Generally I judge customer service on a few specific entities. First of all the person should show genuine interest in my needs giving me some options ans selections.
I think that most of us can tell the difference between a person who is interested in your request and not their own agenda.
Secondly I want the person me to have knowledge about the product that I am interested in or at least be willing to expeditiously provide the information that I need.
Honesty and courtesey is a quality that I expect in customer service.
Recently I was getting bids on a personal project and asked the bidder several questions concerning his expertise; apparently he did not like my questions and gave me a disrespectful answer. Consequently I did not use his service.
It does not cost anything to be polite.