JT asks why publishers so often seem to buy books with hooks and provocative openings... when the rest of the book fails to live up to that.
My sort of answer-- well, you know, quality is often not the primary consideration when it comes to publication of a book. :)
But... well, think about what makes YOU buy a book. I'm a blurb buyer, so hooks really work with me. I've trained myself to read a random page in the middle of the book to make sure I can stand the writing style (and that the mechanics pass muster), but by the time I get far enough to realize the plot doesn't fulfill the promise, well, I've already paid for the book. I don't doubt some publishers count on just that-- that the readers won't know there's a problem when they're ponying up the $7.95. Of course, disappointed readers tend not to buy another book by that author. But if short-term revenue is the most important consideration, the longterm reputation of the author (or the bad reviews, or bad word of mouth) doesn't matter all that much, does it? And how many of us have blamed the publisher? I have to say I've seldom thought, "Boy, I'm never going to buy another book published by --- House." Or "I'm going to find out who the editor was, so I can avoid all other books edited by him or her." Who do we blame? The one whose name is on the front cover.
So I guess the message to writers is: If YOU care about your longterm reputation, about whether readers are happy or disappointed with you, with what's being said about you and your book on the blogs and in the reviews... YOU are the one who has to make sure your book reflects your best ability as an author. You have to be the one who cares the most about that, and you have to be the one who makes sure that's true.
And if you have had the good fortune to encounter editors who reject your less-than-terrific-all-the-way-through stories, well, you should thank them profusely. :)
No, really, there are many reasons a story is rejected, and "the story doesn't live up to the first chapter" is only one of them. How can a writer know if that's the case, so he/she can improve it? What's great is if you know that's the problem, you can do something about it-- there's not a lot you can do about a lousy market or a dying line.