I see a lot of people try to rush and get 30 posts to get into the stories section, then once they get in never hear from them again. There are some very good stories in there that have taken time to write. Those writers deserve just as much encouragement as the writers that are posting stories in the general form.
I've said it before, one of the best ways to get enough posts to get access is to write a story. I know that not everyone has the ability to write a good story. It takes practice and you will get better as you write more. Some of the most prolific writers on here have had stories that nobody seemed to comment on, until someone comments how much they liked it years later and wondered why it was never finished.
Your first story will probably not be your best story, but that doesn't mean you shouldn't try.
If I sound like I am repeating myself, that is because I am. I have the largest collection of braces-related stories on the internet, so I know just how bad some of the writing can be. I have also seen some very good writers that have disappeared because nobody bothered to take the time to say anything. Having another writer comment on one of my stories is greatly appreciated because it shows that I am writing something that appeals to someone who knows how much effort it takes to write. Having other people say that they liked one of my stories is just as greatly appreciated, and can do more to motivate me than they know.