I think he did this because it is more mysterious that way and keep people interested. It also makes the reader have to read between the lines of the text in order to fully understand what is going on.

maggy's blog

Why did Edgar Allan Poe write the story in a confusing form, by which he said that the main charecter was going to murder Fortunato, but then they were friends within the story, but then he ended up murdering Fortunato?