Even worse, they might tell others not to do business with you. Unless you have a unique product or service that only you provide, you have competition. Your level of customer service can make the difference in someone buying widgets from you or buying them from someone else. Make each customer feel as though they are your most important customer. You'll find that they will return and, in most cases, they will also send others to you.
Every business has to have employees, even if it's only one.
No business can run itself. This is very important to remember. You must run and handle your business professionally. Some small business owners, especially home based businesses, seem to forget that it's still a business. Establish your hours of operation and stick to them.