Oh, that's easy: because I'm submitting them. More interesting is why I'm submitting them: I've long waffled on whether I should routinely submit my stuff to HN because while one or two submissions did well, most of my submissions sank without a trace. The obvious thing to do in this situation is to test it out systematically, so for the past few days (and until such time as I get bored with it or run out), I've been submitting 3 links a day: 1 link to a good gwern.net article, and 2 links to non-gwern.net articles which I liked a lot.