Many of my students have labored under the assumption that if they were captivated by an idea, then merely writing it down made it sacred. I call it the "from God to me to the page" theory. In nearly every case, work presented for a grade that went through this process is far from being what it can be. (Note: this is my euphemism for saying that the work tends to be lousy.) And why shouldn't any first draft be lousy?
Hemingway talked about first drafts being shit. Anne Lamott even devotes an entire chapter from her book Bird by Bird to the notion that first drafts are shitty. So why then do many students feel that they are immune to this process?
Maybe it's just the assumption that writing is much easier than it really is. Because many of us have had the luxury of reading a really talented author, we take for granted that what they are doing is something that is easy to replicate. For a child watching a marionette show for the first time, the idea of jiggling a doll on some strings seems painfully easy--as if there is no real art to the craft. All it takes is getting tangled in the strings to recognize the complexity of such an act. Metaphorically, many writers get tangled in language, plot, setting, and dialogue, but because they can't visually see those things, they figure that their ignorance of those things is not a sign of deficiency but instead a sign of their budding genius.
I guess that is the double-edged sword of writing though: when you are really good at what you do, it does come across as painfully easy to those outsiders looking in. They don't see how you wrestled with POV for several weeks or how you wrote a hundred pages, only to start over and write from a different character's perspective.
But this post is not designed to slam or belittle newbie writers. In fact, it is designed to do the opposite. It is designed to remind writers of the significance of the editing process and how one must approach this process with a completely open mind. No sentence is too sacred, no joke too funny, to be cut out of the final draft. Everything on the page must justify itself. That includes each word and punctuation symbol.
I'm not even saying you have to be a master of all of these elements, but if you're going to call yourself a true writer, you, at the very least, need to be a student of them.