Google search occasionally shows a "block results from this site" option but I am not sure when/why. I tend to always be logged in to my Gmail/Google account and like that it can personalize based on history and preferences, but rarely see this option. Why? How do I enable it when it's missing?
Lots of websites are designed to rank high in web searches on a wide range of keywords, but actually turn out to be useless to the person searching for information. You begin to recognize such a site by its increasingly familiar template-like appearance, having visited there and been fooled many times before, sprinkling and linking back your search keywords all over the page.
I would gladly list a few frequent offenders as examples but don't want to create flame-bait.
I just want to finally block those sites from all my future searches, but it seems that feature in Google Search is never available when I'd finally intend to use it to add to my blacklisted/spam sites.