Sarah Monette talks truth to power about The Art of the Short Story. This is actually an article in the sporadic series with a longer title of "Routes to Publication May Vary According to Your Talents" being written unconjunctively by many authors on many blogs.
But she speaks a lot of truth. The first paragraph is what I'd like to discuss, though. In there she says that, basically, Short Stories aren't the same species as Novels. This is a fact. She also discounts the "business route" of writing shorts to make a name for yourself and then start writing novels. This is also true. However, this is the route I've taken. And I think there's a lot of established authors and editors who add on motivations to my move (because they've advised me against it).
I think my natural writing length is a novel. I started out wanting to write novels and I still do want to write novels (as I hope to be working on them this year). Also, novels are where the money is at in this game. So, yeah, novels it is.
However, as my first attempts at writing them showed, I didn't have the foggiest clue as to how to tell a story. I took a community education class taught by a somewhat famous romance novelist that was supposed to help us write novels. It was that experience, the wrestling with the opening chapter, that demonstrated to me that I needed to learn some craftsmanship.