I'll preface this by saying that no publisher buys a book with the intent to provide shoddy editing. But the reality can be that, if you turn your book in on time or early and another author turns hers in late...you get moved up a month. This can be good; don't get me wrong. But this can also mean that your book doesn't get as thoroughly edited in the rush for time.

Some publishers are notorious about rushing books to production. Where publisher A might leave themselves 12-18 months from the day the book is turned in until publication, publisher B might only allow themselves 6-9 months. The result can be a frustrating lack of quality for you and the reader. 

This is exacerbated when typesetting of the book occurs. Usually when you turn in a manuscript to your publisher (I'm talking print here), they want a copy or two of the manuscript and some soft copy (like on disc or CD). If they don't use the soft copy you provided and hire someone to retype it instead, watch out! With some publishers, you reading the copyedited version of the manuscript is optional, and you have to ask to read that. At that stage, you can comment on their changes, make additional changes--whatever is needed--at no penalty. If you don't get to read the copyedited version and are forced to wait for galleys...well, if you don't like their changes, getting things STETed (or put back the way they were) may cost you money. That's because at galley stage, the book has already been typeset and getting changes forces them to have the typesetter redo things. Typos are exempt from this--they won't charge you to fix their mistakes, but I have this theory that changes of any variety at the galley stage are less likely to happen because it costs the publisher money, typo or not.

The short lesson here: Ask to read the copy edits. Read them thoroughly. It's really your LAST chance to change the book. When your galleys come, concentrate on typos. 

Another point I should emphasize is that copy edits are usually freelanced out. These are not actual employees of your publisher, but people they have hired to read, check, grammarize, etc. the manuscript. Some are wonderful with light, deft touches and small margin notes that make you go Doh! Why didn't I think of that? They can save your ass from time to time if you've done something less than bright and they are on the ball. Then...you can get the frustrated writers. I have a friend who did a mystery trilogy. All through the first manuscript, the copy editor  made snide comments about my friend's heroine. The worst came toward the end of that first book, however, when the copy editor made all kind of suggestions for scenes to cut and REWROTE THE LAST CHAPTER. Why? She said if the author would have stopped wasting space on this sniveling heroine, she could have solved the murder at the end of the book instead of leaving the reader hanging. Okay, discounting the fact it wasn't the copy editor's book, the other issues were there were 2 more books in the series and the real killer hadn't even been introduced yet. He'd been discussed in passing. Period. The copy editor rewrote that book so that one of my friend's future heroes was set up as the killer in some rage over another man touching his woman. Um, in the next book, you learned that "killer" was the woman's brother. So he wasn't touching her like that. My friend was horrified, and the publisher agreed to make it right, but even when that book came out there was all sorts of errors left over from this copy editor's attempt to "fix the book."

Distribution is a whole topic in itself. A frustrating one. It's one of the best kept secrets in publishing. You've probably guessed that the farther up the food chain an author is, the better distribution s/he gets. That means not only more copies per store, but in more stores in general: airports, grocery stores, drug stores--and Mecca: Wal-Mart. Wal-Mart sells a TON of books, but they sell mainly category and lead titles. If you're starting out, it's hard to get into Wal-Mart. Distribution at Waldens and Barnes & Nobel, BAMM, etc. will all be decided by chain store buyers you've probably never heard of. The Waldens/Borders buyer is one of the more accessible. B&N, BAMM and the other guys... no.

Amazon is another sore subject. It's tempting to try to determine the success of a book by looking at the ranking. But Amazon is about 2-3% of overall book sales, so it's not that relevant. B&N.com ranking is at least a combination of online and brick/mortar store sales, so it's more relevant. But in terms of affecting overall distribution... It's hard to do. Sending promo items with the publisher's sales force or buying gifts for them, reaching out to chain buyers or local stores--it's all been tried. At the end of the day, as trite as it sounds, you've best bet is to write the best damn book possible, pray for a good cover, and hope for publisher support. Sometimes you'll get it...sometimes you won't.