Nearly 60 percent of people find Web sites from search engines, much of which may be driven by SEO, or “search engine optimization” — a new-economy acronym that refers to gaming Google’s algorithm to land top results for hot search terms. In other words, many of these people have been essentially corralled into clicking a random link and may have no idea why they are visiting a particular site — or, indeed, what site they are visiting. They are the exact opposite of a loyal audience, the kind that you might expect, over time, to inculcate with your message.