Namely, because each user gets one vote, having 100 users want to give your post 1 point is more valuable than having 10 users want to give your post 10 points.
As long as you've got enough technical depth that people will give you 1 point, it's appealing to a broad audience, not catering better to a core audience, that will get you to the front page.
Hence, there's no room on the HN front page for an article that turns a 9/10 Whatever user into a 10/10 Whatever user - only for articles turning a non-user into a 2/10 user, with little to interest a 9/10 user.