I think a key element in writing a short story or novel is portraying a certain style which describes you. Whether it's Tolkien's perfect detail or Rowlings uncanny humor...these authors have found their niche and it's important for us, as aspiring writers, to find our niche.
It's taken me years, and some more, to find my niche in genres, as well as my own style. Best piece of advice I've come to accept, failure is your life lesson. You learn more from it then success.