Nothing, do that! It's not just about Show HN. If you're asking for feedback you're clearing a lot of the problem right there. These are not who I'm talking about. You cultivate some measure of taste right there actually, just by trying to learn about the people you are potentially building for. I am talking about people who post here, reddit, twitter, reddit again etc etc and never ask for feedback they assume their stuff is a gift to the rest of us.