A good story doesn't need to be novel length. In fact, a compelling narrative can be just a few words. In marketing copy, it should be.
Good marketing communications should tell a story. It should evoke emotions. It should lend credibility to its source, and should compel a person to action. This is the biggest piece - we are talking business communications here. Without inspiring action of some sort, marketing communications is just noise.
Sales and marketing are often seen to be the same beast. This isn't true, but sales and marketing can't be viewed in isolation from each other either. We all have "something to sell". If you aren't successfully compelling someone to take action towards you, then you aren't successfully marketing yourself, and you aren't selling anything.
Tell a story. Involve people. Give them the opportunity to be a part of your story. Build a relationship. Sales is like the first date, or the consummation - but don't ignore additional opportunities to build trust, curiosity, enjoyment and passion.