most posts do not show up in the front page at all, the ones you're seeing are the ones that are actually good (in an ideal world, in reality a lot of this is controlled anyway). But yeah even if you make the best thing you've ever dreamed of, do not think posting it on HN = automatic front page. Most content never makes it and gets like 1-2 upvotes. I've hit #1 only once even though i post regularly. Just as long as you're not spamming or breaking any general rules it's alright to take a chance with anything you deem interesting or worth tinkering with.