Ever noticed how when you see something frequently, you stop noticing it?
Your nose's profile, for example.
It makes you think...
the subconscious still sees it, but it pays little attention to it, and the conscious ignores it.
the subconscious chooses to ignore anything that it thinks is unimportant, like your nose (which is important, whereas being aware of it isnt).
i would imagine, there is a massive number of things that you ignore, and of them, some might have greater importance that you dont recognise. i think its silly to try to go over them all to find the importance though.
and then you have psychological repressions, things that do attract attention enough to be conscious about, but that the subconcious knows not to allow the conscious to become aware of. many fears and emotions are ignored because what is gained from ignoring them is more important that what is gained from being aware of them.