Tell a good story, tell it well, and it'll sell. It's said all the time on these boards when writers come in talking about 'what's selling well' and 'what do they need to focus on to get published' and 'what elements make a sellable story these days?'.
So. Either Fifty Shades is a good story, told well and now it's selling, or it's a cash cow the publisher is milking for everything it's worth.
I can only speak for myself, and I came to these boards pre-broken in a lot of ways, but the message I've taken away from AW is "tell a good story and tell it well, and its odds of selling are better but still not guaranteed."
Furthermore, sometimes the fickle finger of fate touches a piece of absolute crap and it sells like hotcakes. It has ever been thus.
It's just that as a writer, I can either wait for that finger to touch my terrible story OR I can improve my own odds by telling a good story well. Since so much else in writing depends on luck (the right editor, the right audience, the right time), I need to focus on stacking the deck in my favor.
Then if I ever get lucky, it'll be with something worth reading and I won't end up as the luckiest one hit wonder to ever walk the earth.
In my day job, I get told a lot that my success has come from being in the right place at the right time. That is true. But I was in the right place at the right time
with the right skills to take advantage of it. I can't help but think (hope?) that writing fiction is the same way.