It used to be that you'd get your traffic from Google. That one good tutorial you wrote would bring a steady stream of visitors for years. But for a few years now Google has a strong preference for fresh. Fresh links matter more than long-standing ones, fresh content will place higher than a more refined, but older take on the same subject... And there's a whole industry of people who spend their days, um, "paraphrasing" what you wrote. Can't win as a hobbyist :(