From “LETTER FROM THE PULITZER FICTION JURY” by Michael Cunningham:

We loved each of the authors for their triumphs over the forces of banality, contrivance, predictability, thinness, falseness, randomness, tidiness, and all the other forces that defeat almost everyone reckless enough to write fiction at all.

That’s a pretty good list of things to look out for in writing. He gave a specific example later on:

A third fell under the wheel (and this one was particularly heartbreaking to all of us) when we reluctantly acknowledged that although it was wonderfully written and fabulously inventive, its central love story, while moving, was insufficiently complicated and a bit sentimental; that it failed to depict the body of darker emotions that are integral to love: moments of rage, disappointment, pettiness, and greed, to name a few. All three of us wished love to be as simple as the author imagined it to be, but we acknowledged that love, as far as we could tell, is not only not simple, but that part of its glory is its ability to survive incidents of rage, disappointment, and etc.