Expect rejection, but hope for more.
That's kind of been my motto since I charged into the realm of writing professionally several years ago. No matter how hopeful you are, expecting rejection results in a feeling of "yeah, saw that coming" if you do get rejected, instead of a world-shaking tumbling down of confidence.
I once had a conversation with someone in which they opined that they were not "good enough" to query the agents they really wanted. They believed they would fail, but furthermore, they believed they weren't worthy. Like, that approaching their legends would be offensive somehow on top of being unrealistic.
But that's not the way to do things if you want to succeed. Expect rejection, but hope for more.
If you never ask the question, the only people you approach will be the ones you feel like you're settling for.
My agent has asked some of the biggest publishers in the world whether they might like to offer on my book. There were times that I almost felt impertinent doing so, like why would a company that's handled multi-million–dollar authors bother with reading my book? . . . but every author starts as a nobody, and all of them are people who asked the question. All of them are people who didn't treat the pies in the sky as if they were above their station.
I've done everything right. I managed to write a book and get an agent to fall in love with it. Instead of asking how it could ever be me, why not ask why not me?
When my nonfiction book sold, my editor and publicist asked for reviews and blurbs from some people and news entities that felt way out of reach. Most of the time we were right in suspecting that they wouldn't answer. But because they did ask those questions, I was surprised to get an excerpt featured in TIME magazine, an interview in the Washington Post, and a mention in the New York Times, as well as a starred review in Library Journal. Some of them they didn't even tell me about until we got a yes because they didn't want to get my hopes up.
My agent is still asking big shots if they want to publish my book. I haven't gotten to yes yet, but I think I will--if not with this book, then maybe with the next one, or the one after that. (I do like to write things. Sometimes they come out okay. I'd continue to do it even if I wasn't trying to sell a novel, so why not?)
I'm still asking pro markets in short fiction to look at my work. I haven't gotten to yes yet, but just because I've only managed acceptances in non-paying, token, and semi-pro publications doesn't mean I shouldn't bother asking pros. Maybe one day someone will say yes to me. And based on how many times I've asked recently, maybe that someday is soon.
You have to ask. You have to try. You can't view these lofty goals as being as far away as the moon, only there for you to bask in but never hold. You have to keep respecting yourself enough to think I'm worth this. And if you're anything like me, even when the big guys say yes to you you'll probably still feel almost a little impertinent next time you ask the question too.
But for people to answer yes, you do have to ask the question in the first place.