Ad Rotation: Rotate Evenly or Optimize?
Google AdWords allow you to choose how your ads show; you can choose to have all ads within an ad group rotate evenly or let Google optimize by showing the “better performing” ads more often. But, Google defines “performance” as the ads with the highest CTR. This makes money for Google, because they are making money every time an ad is clicked, so showing the ads that get clicked the most makes sense. But, what about conversions? You may define “performance” as ads with the highest conversion rate, not ads with the highest CTR. There are many reasons why you may or may not want to optimize your ads. Here are a few pros and cons to help you decide:
Even Rotation
Pro: You have control of your ads and define “performance” how you choose.
Pro: You can fully test which ad variations for many factors besides CTR – also for conversion rate, ad text, landing page success and more.
Con: AdWords looks at CTR when determining Quality Score, and a higher Quality Score means better ad position and a lower CPC.
Optimize
Pro: Because AdWords does a great job showing the ads with the highest likelihood of being clicked, you can quickly tell which ad has the best CTR, rather than waiting to see results with even rotation.
Pro: Continually showing the ad with the highest CTR results in a higher Quality Score, which again, means better ad position and a lower CPC.
Con: You may end up spending money on ads that aren’t converting.
The common school of thought is to maintain full control of your ads and the ability to test them by choosing even rotation. That said, you may choose to start your campaign on optimize to let Google tell you the ad with highest CTR quickly while improving quality score. Then, with that information you can tweak ads, based on what worked while on the optimized setting, then switch to even rotation to fully test all ad variations.