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.
(..) We will be on our own. The Enteprise has something no other ship in the fleet has. You. As we can't understand there's no such space, the unknown. We'll be temporarily hidden. Kirk out. Readings indicate cloud density deminishing, sir. This is Altamid. Our ship is stranded here. Approaching Altamid. Class M planet. Massive subterrenian fauna, with unlimited unknown life forms on the surface... Proximity alert, sir. We have an unknown ship heading right on us. - Lt. Uhura, hail them. - Yes, Captain. No response. (..)2016 Star Trek Beyond