In theory Lookalike audiences based of pixel / catalog data are dynamic, meaning they’ll change over time as triggered events occur. In order for your account/campaign/adset/ad to properly learn, you’ll need a minimum of 50 triggered events in a 7-day window. When you see terms like “learning limited”, there can be multiple reasons for this error, but most likely the reasons due to not enough spend allocated toward that adset/ad. To work backward on how much you need to spend to hit those triggered events you’ll have to start with the average Cost Per Conversion multiplied by 50 to get your weekly budget. (And that’s real cost, not what you feel like paying for a conversion) So spend X budget to hit 50 conversions, in a 7 day period, and learning will occur - making your Lookalike audiences that much more powerful.
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