Once your story is published, its words are available to the public forever.
I think the above sentence is what people fear. Although we strive to publish our novels, when the days actually come for our books to be released into the world, we get scared. Some of us never have the courage to go through with it. We may know we want to self-publish or find an agent, but we're too scared to try because what if people hate it? I think that's a mistake.
We want our stories to be perfect. Many authors are scared of making a fool out of themselves through their book. They get depressed and sometimes embarrassed when they receive one or two star reviews. If a book receives too many negative reviews, they are afraid that their careers are ruined.
I self-published my first novel back in November. My book isn't perfect, but I do not regret self-publishing it. I've learned so much about writing and marketing since I first published my book. The one problem with writing book after book without ever publishing is that sometimes it's harder to grow as an author that way. Now that I'm releasing books and getting direct feedback from readers and through numbers (of what I'm selling and what I'm not), I know more how to please them.
Just like my critique partners improve my writing, so do my readers, even the ones that hate what I write.
No one is a perfect writer. There's always something to improve on and work harder at. It's always difficult to find readers for your book, whether there was recently a best seller with a similar idea or there's never been another author to write something similar. Trends come and go quickly, the marketplace changes at breakneck speed.
There's a million reasons why logically you should *not* publish. But we don't write because it's logically the best thing to do or will make us the most money. We write because its what we love to do. So follow your heart and take a risk. Your mind will catch up and fix your mistakes as you do so.
The best way to improve is to try. Making mistakes will only help you grow.