Employees should be dressed and groomed well. Think of these points as implied agreements between your customers and you. Once we know these agreements, we can organize and train ourselves and staff to meet our customers' desires. Periodically survey your customers to find out what they really expect from you. Personally, it bends me out of shape when I have a question to ask and there's no way to contact anyone.
Reliability implies accountability in the event of problems.
Yet, too often, web pages are designed to obscure all lines into the staff of the company, excepting only the sales line. Autoresponders are just not enough. A company's attitude toward its web customers shows in how hard or easy it is to get an answer to a tough question. Recently I tried to buy a network card for my Dell laptop. Here's the name of some third party vendors who might.