If you've never been published before, you're an 'unknown quantity', so you're going to have difficulty selling your first novel.
('chiefly US') The 'big unknown' [=the important thing that everyone would like to know] is how investors will react.
A 'fear of the unknown' kept her from changing jobs.
(..) How much? You're silly. Well, there's something. There's a particular touch to it. But I mean... . ' for an unknown artist seems like a lot. Hmm... On the other hand, if I don't buy it it's going to be worth the triple in a year... And you'll tell me: "I told you". Am I right? (..)2011 The Intouchables