While there is often a word count for short stories, there are exceptions to this word count. One such exception is Joseph Conrad's story, "The Secret Sharer." This rather long story, nevertheless, exhibits the main element that classifies such narratives as short stories: a singleness of direction towards which theme, plot, character all direct themselves. Poe describes this as "a certain unique or single effect to be wrought out."
Using Conrad's story as an example, the plot and theme are all directed towards the point that the mirror-image of the stowaway allows the author to explore different sides of the captain's identity. In fact, each of the two men gains insights into his own character through his relationship with his "secret sharer."
Thomas Hardy wrote that a short story is "a tale of experience [that] would dwell in the memory and induce repetition.” The short story does not divert from this purpose as so many novels do frequently. Indeed, it is a tale of a single experience in which the narrator takes a greater role than in other fiction, resulting in a strong turning point that effectively impacts those who read it. This unified effect is what Poe contends all stories must possess.
short story is the story which can be read in a one sitting.
and its lenght could be as long as its limit