An informal poll of aspiring and midlist crime fiction writers (and by "informal," I mean that I've completely made this up) shows that when a manuscript fails to find the right publisher (and by "right," I mean "any"), the writer quite often attributes this sad circumstance to poor marketing strategy or incompetence on the part of the agent involved. In some cases, a writer trying to find representation will assign blame in the same fashion: It's the agent's fault.
No. It's not.
The fact of the matter is that in most cases--and again, this is based entirely on research that nobody has done--when a manuscript doesn't sell, it's due to one of two things: Either publishers sincerely can't find a way to market the work and think they won't make their advance money back, or the manuscript just isn't as good as the author thinks it is.
Guess which one is more likely.
There is a definite rush to finishing a book. As a writer, you look back on what you have accopmlished and are slightly awed by it--look at this thing you wrote! It's long, for goodness sake. It has a story, and characters, and maybe even dialogue, and did I mention it's really long? It took weeks/months/years to complete, but you muscled through it and now it's done, and you should, at that moment, open a bottle of whatever comes to mind (anything from Dom Perignon to Yoo-Hoo, whatever works for you) and savor the feeling. Hail the conquering hero(ine)!
No one can take that moment away from you. If you persevere to the end of an epic adventure like that, you have already achieved a great deal more than most who set out to do so. You should, indeed, be proud of yourself. You should recognize the accomplishment and find someone to pat you on the back (or whatever floats your boat--I do not judge).
But don't get a swelled head. Just because you've written a novel-length manuscript does not mean that you have necessarily written the next great literary sensation, or even something that can sell for $1.99 at the yard sale. Don't get caught up in the moment to the degree that you stop being at least a little objective about what you've done.
Lots of people have written books. Not that many of them are Herman Melville. Or Janet Evanovich.
Most first novels, to be honest, belong in a drawer. There's no shame in that. Second novels are usually better. Or second drafts of first novels. Or first screenplays Or first graphic novels. Sometimes you need to rethink the whole concept from the start and go with what serves the story (and more importantly, the characters) best.
So how do you know if your book is ready for submission? First, take a week. Better, take two weeks. Do something else. Go scuba diving. Read someone else's book. Take tango lessons. I don't know; go to work at your actual job. Take your kid to the beach (if you're not me--I'm not crazy for the beach). The only thing you should definitely not do during this time is read your manuscript again. You won't see it; you'll only see the triumph of time and effort and not the result.
After the two weeks are up, open the file again. Read it with OBJECTIVE eyes. You'll see flaws. You'll notice things you wish you hadn't done. You'll despair for the puny, crippled thing you have created.
But having seen all that, the good news is that you can make it better. Plot possibilities that hadn't suggested themselves because you'd had a plan will appear. Character traits will surface that you can exploit more thoroughly. Mistakes can be corrected and style stengths added.
In other words, once you can see your work clearly, you'll have ideas on how to revise it. Do that.
After the reworking is done, take another few days and start working on something else. Then look back again and see if there are more horrifying errors that can be smoothed over and repaired. And go ahead with those fixes.
Now maybe you think your book is ready for submission to an agent or a publisher (through an agent). If so, let two people who don't love you just for yourself read it. See what they say. See if you agree with what they say--if their name isn't Marilyn Stasio, your opinion is as valuable as theirs.
If you think they have a point, get back to work on rewrites. If they like what you've done and have no suggestions, good. If they have some suggestions you think are stupid, feel free to ignore them. This is, after all, a free country, although the bills have gotten quite high.
When your work is in the most pristine, as-close-to-perfect form you can reasonably conceive of, it's ready for the rest of the world. Get in touch with those who can help move it forward, and take your chance. Maybe you'll get a call that a publisher (or better, more than one publisher) is interested. You're on your way. Or, you'll find that even with good represenation and a coherent plan, your work simply isn't going to find a publishing home.
Now, it's time to blame the agent. Josh?