A Question for Readers: How much does quality, professional writing matter; or is the story ALL that matters?

I've jumped into a discussion at The Passive Voice blog, and I'd like to expand on it here. I'm really gearing this question towards readers, but I welcome comments from writers too, provided you first put on your reader's cap.

We all love great stories. That's a given. However, is that all that matters to you? What if it's poorly written, laden with grammatical errors and poor structure? Does that matter to you? How much? Where do you draw the line and forgive an author for poor writing?

Does moving, eloquent prose move you as a reader? If so, how much will you forgive a less-than-thrilling story?

Okay, so that's more than one question… sort of two sides (or ten) of the same coin.

Please, I'd love to know your opinion on this.

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