Typically, recouping losses means bringing in new searchers: once enough new searchers convert, they compensate for the non-converting ones. But even when coupled with overall improvements in your conversion path (like getting better ad copy, landing pages, and customer segmenting), the strategy is still inefficient. First, click-throughs are expensive; and so paying for more of them isn't the cheapest way to make up for poor performance the first time. Second, your new wave of searchers will also include non-converting visitors--which means that, by trying to solve this problem, you're creating the same issue all over again.
A much better bet stems from the basic efficiency principle that, often, it's easier to improve what you have than it is to start from scratch. Which is why, rather than starting over, it's cheaper to get those "lost" searchers to finally convert.
That's the theory behind behavioral search retargeting, a new search method. (disclosure: my company is among those offering this service.) The premise goes like this: once a searcher has left your site without converting, you use display ads (banners, skyscrapers and the like) to follow her around the Internet, until she clicks on your ad and comes back to you. Since she's entered your site before, she's probably interested in the kinds of things that you sell; she's also likely to recognize your brand. So even if she didn't convert the first time around, she's likely to click on your display ad at some point--and studies show that lost visitors who revisit within 72 hours are very likely to convert the second time.
(The name "behavioral search retargeting," by the way, means that you're retargeting your advertising to lost viewers in a new form, based on past search behaviors--like their clicking on your ad in the search results page.)
Not only is behavioral search retargeting strategically efficient, it's also cheap. That's because display ads, on the whole, cost a lot less than search ads do. To give one example: if a keyword costs $1 a click (which is on the lower end of prices for best positions), and you've got a 2.8 percent click-through rate (which is average), you'll pay $28 for 1,000 impressions. Compare that with the very upper end of the display ad scale, in which you might pay $15 per 1,000 impressions. And since you're advertising to people who are already likely to recognize your brand and your product type, you can get your ads to pop at much less coveted--and much cheaper--areas of a given site page.
In other words, you get to recoup a lot of your losses, at a much lower price; meanwhile, you're assured that, sooner or later, a much higher percentage of the clicks that come in will ultimately convert.
A final, somewhat philosophical word. While all of this might sound like a bold new move for search, retargeting is really the logical next step in a broader evolution. Search began as a field about engines alone, but it's becoming a field that's as much about conversion architecture as it is about keywords. That's only natural: search is the bridge that ties initial interest with final conversion, on nearly every conversion path. It includes the tasks of picking up traffic driven by TV spots, word of mouth, and generic needs; and driving that traffic to convert through Web sites, call centers, and bricks-and-mortar stores. And so search success is determined by how well you're able to coordinate your traffic, at every step of the way.
Which is why getting the most out of search is as much a matter of overall conversion paths as it is a matter of bid changes; and why addressing the ways search impacts post-site behavior is a logical next step in where search takes advertising next.