Even though a site may receive heavy traffic as a result of online media, most visitors typically arrive via direct or non-paid search rather than via a landing page or campaign. So although a majority of efforts and resources may focus on tuning campaigns and landing pages and on converting visitors who arrive through those channels, they're usually only a fraction of the audience. I'm not saying don't spend the time on optimizing campaigns and landing pages. Actually, I'm saying just the opposite. Keep doing it if you're doing it, but do the same for the rest of the site.

There are costs tied to both campaigns and the overall site. These may include development, management, hosting, copywriting, and design. Even more important is the opportunity cost that's lost by not converting site visitors when they arrive -- no matter how they get there.

People who access the site directly often behave differently than those who access the site through natural search and ad campaigns. Also, different search strategies and different campaigns often perform very differently.

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