When a user does a search, clicks on a result, that result does not have what they want so they hit back, and then they click on another result that is a failure of the search engine. "Users can decide the site is worthless after they click" is an opportunity for somebody to come up with a better system.

I guess I simply don't agree. The search engine should give me the best information, period. It does not, and one of the reasons it does not is because it is busy prioritizing things that aren't relevant to content.