Let me tell you right now, if you just finished writing your story, literally just put your pen down, or took your fingers off the keyboard after typing "The End"... it's not good enough.
Even if you think it's the next Harry Potter, uhuh. Set it aside for a day, a week, a month - the longer you can keep your fingers out of it, the better. Especially if this is the first story you've ever finished and you are just so darn excited and want to get your masterpiece out there - don't do it!
If you proofread it right away, guaranteed, you will not see any of your mistakes. You're too wrapped up in it. The story is still alive in your head, so any gaping holes in the plot are all being filled in with what you already know...and they may not actually be written down.
Yes, folks, this is experience speaking.
So, you've given it some time and you go back and read your story. And you think, it's pretty good - that's not good enough!
If your mother, your sister, your cousin and your best friend have all read it and said "It's good"- it's not good enough.
If no one has said, "Wow, that's great!" and if you can't say that yourself - then it's not good enough.
Okay, so now it's time to get your red pen ready. Find a good critique partner - someone who's not afraid to cross things off and tell you how bad it really is. Cause now it's time to get to work and polish, polish, polish and yes, rewrite if that's what it needs.
So set aside that story you just finished - start another one, or read a few books. Just don't touch that story until your brain can't tell you every detail about what your character was wearing, or saying, or doing, or thinking especially.
Don't touch it. Don't send it anywhere (except maybe a critique partner, but it's not even ready for that at first, probably). Let it lie - unless you're anxious to see your next rejection letter.
If you can't say it's great, then it's not good enough!
Until next time...