Length

• Not all interesting story ideas are complex enough to build a novel around. Novels typically require several characters, subplots and multiple plot points. With a short story, a writer can stay focused on the one character or incident that interests her. Even though it often takes many revisions to create a good short story, the process is still much faster than writing a novel. A busy writer may enjoy the sense of accomplishment she gets from completing a story in a few weeks or months, as compared to the years it can take to complete a novel.
  
  

Publishing

• There are many more opportunities to publish a short story than a novel. Print and online literary magazines, anthologies, short story collections and contests are a few of the options authors have when looking to publish shorter works. Though the financial reward for publishing short stories is relatively low for most writers, being published can be its own reward when a writer is trying to build a portfolio or attract readers for other projects.
  
  

Discipline

• Short stories require a slightly different set of writing skills than novels. Short story writers must be more compact in their writing habits than novelists, without sacrificing character development, conflict or setting. A writer who is trying to develop a leaner, clearer writing style might devote himself to short stories in order to hone his craft.
  
  

Love of the Format

• Some authors prefer writing short stories because they prefer reading them. The best short stories start near the end of the tale and manage to create interest and tension within a few sentences, paragraphs or pages. Some writers find this type of literary challenge exciting. Also, the perimeters of a short story are flexible. An entire short story can be only a few paragraphs long, as in the genre of flash fiction, or it can be many pages.