It's very difficult for a publisher to take on projects that aren't already highly polished if they don't have editing staff to support them. As anyone who's tried to edit their own manuscript knows, it's a HUGE amount of work. There are layers and layers of editing, ranging from spelling, grammar, and punctuation, to tweaks of story arc and character integrity, to full character development and storyline revisions, requiring scene cutting, scene additions, and rewrites of chapters. This applies to the work of almost all writers, no matter how articulate they are. Editing is no place for sissies. Professional editors in publishing houses tend to have spent many years learning to be editors and typically have college degrees in editing or related subjects.
I believe it was a mistake for publishers to cut their editing staffs. It may have lowered their costs, but in the long run it made them less competitive. I also believe there isn't a substitute for quality editing when it comes to developing outstanding novels. So how can we get the editing we need to make our manuscripts topnotch if we don't have a publisher with great editing support?
We can hire editors ourselves, and many of us do exactly that. But most of us can't afford to pay the prices top professional editors charge (and deserve)—easily $2,000 for a 350-page manuscript, often twice that much, especially if the manuscript requires a lot of work. There's also the built-in potential for conflict of interest. An editor you are paying may not be entirely comfortable giving you in-depth, honest criticism and advice on your manuscript (especially if it's not as well-developed as you think it is, an all-too-common occurrence). This is often raised as an obstacle to objective editing by author-paid editors.
It's a complicated topic, but here's my viewpoint: we owe ourselves topnotch professional editing to make our novel the best it can be. If we've taken the manuscript as far as we possibly can, and truly believe in it, but are still not getting a sale to a publisher (or if we intend to publish independently) we need an excellent editor to help us put the final touches on it.
What's your viewpoint? Do you hire professional editors? Do you think there's a good middle ground? Maybe great crit partners do enough? Or less expensive, less experienced editors who still provide valuable input? Or perhaps if the novel doesn't sell over a period of time, we should simply put it away and move on to a new project?