One of the things I enjoy the most about being self published is the lack of pressure. Any deadlines that I have looming before me are completely self-imposed. The only reason to conform to current popular book genre trends is to make money. So the genre that you write is, again, self-imposed.
This really gives one the freedom to write that story that wants to be written. The sole reason why I did not want to study literature in college was that I hate being forced to write about topics that do not interest me at the time.
Non-fiction I can somewhat handle. Even if the topic is dry, there is some enjoyment is learning new facts during the research process. But it still didn't completely dull the throbbing headache as I stared at my computer screen late at night trying to find some way to turn my six page essay into a ten page one.
I could only imagine how fiction would have been worse. Being forced to come up with characters, plots and twists for subjects that you can't abide. And all due tomorrow!
I think true creative writing is a process and not one that can be forced. Ideas have to sit for awhile and ferment in your head. My policy is that if you pull the idea out and and it doesn't flow easily from the get-go, it has to go back and ferment some more. Every time I've tried to "force" a story, I regret it and end up deleting most of what I wrote.
E-book publishing is a fast business and there is a pressure that we tend to put on ourselves to produce works quickly in an effort to keep up with the competition. But don't cave in! Short stories get enough guff as it is. Make every effort to have each story be your best work.