In traditional marketing, "ad burnout" describes a decrease in ad effectiveness over time as ad exposure frequency exceeds certain milestones. Ad burnout has been measured both around specific creative units (the same TV or print ad) and individual marketing messages (this is why soft drinks change their general ad message every few years).

Ad burnout has never really been a problem in PPC (define) search marketing. User behavior generally limits the number of times searchers are be exposed to an ad. Even if you run a combination of generic and specific keywords in a campaign, chances are your creative is slightly different to take advantage of searchers' differing states of mind, as expressed through keyword choice. You might even have the opportunity to expose searchers to a tuned ad message several times during their prepurchase research.

Yet, text link ad burnout will become an increasingly important factor over the next several years. Perhaps it's already an issue for you. Emergence of contextual networks in the PPC engines running parallel to the search networks raises the risk of ad burnout.

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