A happy customer is more valuable than any investment that you make in your advertising program. One happy customer could turn into multiple customers. It's called customer evangelism.
On the other side of the customer coin is negative customer evangelism. Here's an example of one customer that's created a community of unhappy customers. Sure, this is a little extreme. But, it happens everyday in neighborhoods and workplaces across America.
A busy work day brings lots of stress and problems. The most important thing that you should do everyday is make your customers happy. The other stuff can wait. It just doesn't seem like it at the time.
Everything has an equation:
Happy Customer + Network of Friends = Word of Mouth Advertising
Best of all, word of mouth advertising is free.