A happy user is a returning customer! There are typically a few things that builds a brick wall to that reality.
For the majority of us, that #1 barrier is a simple and efficient means to solve a customers problem or knip an issue in the butt before it gets out of control.
Contrary to popular belief, this doesn't always have to be a one way street. By empowering your customer to reach out to you, or providing them with the resources necessary to solve their own problem - you can literally manufacture an army of happy users!