06/18/2026
The best Sponsored Display campaign in this account had an 8% ACoS.
Claude told me to shut it off. It was right.
Retargeting ACoS sat at 8%. Conversion rate looked beautiful. On paper, the campaign was carrying the account.
Then I pulled the new-to-brand split. 91% of those sales were repeat buyers. People who had already bought from me. People scrolling Amazon who would have clicked the listing anyway.
I was paying Amazon to intercept sales the listing was about to win for free.
That's not retargeting. That's a toll booth I built on my own driveway.
I broke the full audit down in the carousel. The exact columns to pull from the bulk report. How to read new-to-brand percentage by campaign. And the three-branch decision rule I use to keep, cap, or cut each retargeting line.
One thing on AI before you swipe. I let Claude pattern-spot the search terms and flag the outliers. The final call on whether a campaign stays alive is mine. AI does not get to decide what gets killed in my account. Neither should it in yours.
Pull your last 60 days of Sponsored Display data this week. Run the split. You will probably find what I found.
Save the carousel and run the audit before your next bid review.
P.S. The campaign that looks most profitable in your account is usually the one stealing the most from your organic line. Check it first.