From the wisdom of literary agent Nathan Bransford comes this important news. The reason why agents don't ask for your manuscript is because your query lacks the right factor.
An agent reads your letter, and if you've said something that resonates with them, you're in. If you've written something that is highly marketable and your query letter shows that you can compose a standard letter in standard English and follow the submission instructions, you're in.
His recent blog post only makes things seem that much more futile. We write what we like, what means something to us, but what happens when an agent looks at the synopsis paragraph of the query and doesn't find the story intriguing? There's no market for the book, so there's no point in not rejecting the query.
You could craft the world's most perfect query, but if a literary agent doesn't get all excited about your story, you're dead in the water. That might explain why so many novels are set in New York City and involve the sort of people you'll never meet in your lifetime because you don't live in New York and hang around with publishing types.
Query widely, Mr. Bransford advises, but you might want to write something that has that resonance factor. Check out the weekly deals listings at Publishers Marketplace and you'll see what's hot. And you'll see why your manuscript fails to resonate.