"What is the most important factor when communicate with customer?

My answer is sincerity. With the experience for years’ communication with customers for our ceramic paper insulation, I do believe this is the truth. 

Days ago, we got an inquiry from a Korea customer who asked for the 2mm thickness ceramic fiber paper used for electrical product production. As this is the new application for ceramic fiber paper in this region, he not sure what type he needed, and not sure the thickness. After knew his usages, we send him free cut samples with all types of our paper in different thickness for testing. Once he got the sample, he called me back and expresses his surprise for the perfect package and details we ‘done on the sample. Although at that time we not offer him price, he said that if it is suitable for the new application, i will order from you and not consider the second supplier at all. 

After the testing, he sent me very detailed description of the testing result. And we offered our professional suggestion toward that. Few days after that, we got his order and positive comment. After his permission, I wrote the copy of his remark here:

As a closing remark I would like to state that both the product AND the customer service I have experienced so far has been trouble free. I feel I can trust this company with my business and would like to do so in the future.

We had become familiar friends now. I once ask him that what makes you choose Double Egret? He answered: “I can feel your sincerity from your sample, from your words, your email. This is the reason.”

So treat your customer with your sincerity, and wrote with your full faith, the mail can talk. They can feel what kind of person you are on the other end of the internet.