Buying traffic · also called creative fatigue, banner blindness
Ad fatigue
Ad fatigue is the decline in an ad's performance as the same audience sees it repeatedly and stops noticing or clicking it.
An ad that worked brilliantly last week slowly stops working. The people most likely to respond have already seen it, several times. The signs are a rising frequency (average views per person), a falling CTR and a rising cost per click.
Fatigue hits search arbitrage harder than most businesses because margins are thin. A campaign running at 25% ROI can slip to break-even through cost creep alone, with nothing wrong on the feed side. Since the revenue per visitor has not changed, the operator may not notice until the daily profit line turns red.
The cure is a steady supply of fresh creatives: new images, new angles, new formats, introduced through creative testing before the old ones die. There is a wrinkle specific to this industry. Under Google's rules for related search, the text of each new ad must be passed accurately with the page request, so a fast creative cycle needs disciplined record-keeping, not just imagination.
An example
Say an ad starts with a 2.0% CTR and a $0.20 CPC. Three weeks later CTR is 1.2% and CPC has risen to $0.27. If each visit still earns $0.25, a 5 cent profit per click has become a 2 cent loss.
Related terms
Creative testing
Creative testing is running several versions of an ad side by side on small budgets to learn which image, headline or angle performs best before spending more.
Creative
A creative is the actual advertisement a person sees: its image or video, headline, text and button.
CTR (click-through rate)
CTR is the percentage of people who click something after seeing it, calculated as clicks divided by impressions.
CPC (cost per click)
CPC is the price paid for one click on an ad; in search arbitrage it is what the arbitrageur pays a traffic source for each visitor.
Ad angle
An ad angle is the particular idea or motivation an ad uses to make a topic interesting, such as saving money, curiosity, convenience or news.