When I started managing my first search engine marketing (SEM) program at Alibris I quickly found that being the first ad on a Google search result wasn't working. It seemed a bit counter-intuitive. The volume was great but the conversion was atrocious. But I had a theory for this phenomenon that I quickly dubbed MonkeyClicks.
My MonkeyClicks theory is that a user tends to click on the first result on the page regardless of whether it really meets his or her needs. It is plain ol' human behavior. A knee jerk reaction of sorts. So you get a tremendous amount of volume. However, that first click doesn't always match the needs of the user and even if it does they will often return to the search results to determine whether other options exist.
If you think of this outside of the small world of search engine marketing it makes perfect sense. If I'm looking to buy a car I'm likely not going to look at the first advertisement I see and then run off and buy that car. If I'm looking to buy a new bicycle on Craigslist I'm going to look at a number of matching results, not just the first one.
This makes sense but lets back it up with some data. (I like data!) Back in 2006 AOL accidentally released a chunk of user search results. It showed that 42% of all clicks on the first page of results came from the first position. In comparison, the second position racked up a distant 12% of clicks.
Another eye tracking study by Cornell, and reported by seoresearcher, showed the disparity in the % of clicks and % of time spent on each search result.
The ratio of clicks to time spent on the first position is a classic example of MonkeyClicks behavior. The first position garnered 56% of the clicks but only 28% of the time spent.
All of these studies are done with natural search results, but I'd argue that the paid results will look very similar. Not to mention that I've seen this time and again as I manage various SEM programs.
However, your mileage may vary! So don't take my word for it, do a quick review of your own SEM program. If you're running a Google AdWords program and Google Analytics, simply take a look at your Keyword Positions report.
And ... beware of MonkeyClicks.