I read an interesting post at literary agent Janet Reid's blog earlier this evening. It gets into why she, as an agent, has to reject people for various reasons, one of them being "I can't sell this." You can get there from here.
Part of one sentence in the post resonated with me:
...and/or the only publishers taking on this kind of book don't pay enough for it to be profitable for us.
I wanted to elaborate on that, speaking from my own experience. Just because an agent/agency doesn't think a book will be profitable for them doesn't mean it won't be profitable for you...or that a publisher won't want to take you on and publish your book.
How does that work? It's simple. There are many excellent upstanding digital first e-publishers with good track records taking on many unagented authors all the time these days. The contracts are basic and if the books sell the author and the e-publisher make money. (The readers usually get good e-books at a fraction of the cost, too, but that's another post.) The only problem is there isn't enough money to pay an agent's commission in most cases. And the authors DON'T need an agent to shop their work to these e-publishers. And that's why it wouldn't be profitable for agents, but it could be profitable for authors who work without an agent.
I know authors who have built good careers in the past few years with e-publishers, and without a literary agent. From personal experience, I can tell you that it can be done. And you can't blame an agent for turning down something they don't think will be profitable.
So while you are querying widely to agents, make sure you learn everything there is about e-publishing...not self-publishing; there's a difference: I'm talking about e-publishing...and query a few e-publishers as well. The markets are growing daily. One of my favorite e-publishers (not one of my publishers) started out with romance and they are now getting into mainstream fiction this fall. They have authors with excellent sales, and a huge readership as well. In fact, from what I've seen this particular publisher is LOVED by readers.
Things are changing in publishing, so make sure you know all about those changes.