Writing is important. Not writing in general. Quality writing in terms of style, prose craft, and so on. If your writing is stilted, overly verbose and flowery, or otherwise distracting, it doesn't matter how good your story is, the reader will quit on you. And heavens help the writer with bad grammar (fiction grammar, not academic grammar) or spelling.
But, good writing will only get you so far. You have to have a good story. You have to have the storytelling skills to keep the reader invested in that story. Writing style is only the very first barrier to entry for a reader.
I ran across a statement by Dean Wesley Smith several months ago, one he repeats many times in his "Killing the Sacred Cows of Publishing" series (required reading, IMHO.) He says that most new writers are concerned with sentence by sentence writing, rather than story writing (any errors/paraphrasing are mine.)
I have been turning this statement over in my head for months, trying to understand it. I felt sure that I, as a new writer, was likely committing this offense. But I couldn't understand how, or how to move past it. How else could one possibly write, other than sentence by sentence?
It's taken two things to illuminate this issue for me. Firstly, the idea vs story concept I picked up form Bob Mayer. That idea in itself has radically changed my writing process. The huge number of words I've written in the last four months has also helped tremendously (about 100,000 or so.) Basically, I've gotten to where I am much faster imaginationally (yes, that's a word. It is now, anyway.)
It took me weeks to write my first story. I could probably (have, I think) write a better story now in an afternoon. Not that I am trumpeting my own horn, or claiming that the stories I write now are great (they are, of course), but they are miles ahead of what I was writing when I started.
I am developing a faculty to see my stories in much broader swaths than I could when I started. And I see now where the particulars often don't matter, as long as they convey the essential story information. It's not the words, it's the content. words are just a container for story.
A humble note - I'm sure (I really really hope) I'll continue to grow as a writer, and understand storytelling and writing better. I hope my current understanding seems as limited to future me as my past me's understanding seems to present me. Phew.