Not all ads need clicking, and the big budgets have never been in generating clicks, but in Branding (like TV ads).
The 10% that click are likely spit somewhere around 50-50 between the least valuable eyeballs (suckers who click ads) and people that actually are interested, depending upon the ad type (Search more valuable, banners less so).
The 10% that click are likely spit somewhere around 50-50 between the least valuable eyeballs (suckers who click ads) and people that actually are interested, depending upon the ad type (Search more valuable, banners less so).