We have to upgrade our skill sets, as well as our programs, constantly as the Internet changes at the speed of light. As professional site promotion specialists, we must employ cutting edge marketing techniques because what worked last year doesn't work so well now. In Internet years, last year is the equivalent of five years ago offline. What worked last year, what is finally trickling down to the public, is now antiquated technology. The techniques you read about are becoming less and less effective all the time as more and more people are using them.
Innovation is the site promotion specialists' stock in trade.
Professionals simply don't share the secrets that make them successful while they still work. Their professional secrets are what keep them professionals. Tired old techniques take a lot of time and effort without yielding serious results, and you won't even know your efforts are futile until you've spent all that time fruitlessly. The information that actually keeps the traffic coming to your site is used first, and innovated, by web site promotion professionals. It's a fact of life that once a technique is adopted by the mainstream, it simply is no longer very effective for getting people to your site.