The problem of reaching current customers when you explicitly exclude them is a common one.
Let’s explore what may be happening…
Excluded Customers
Maybe you used an Existing Customer Budget Cap with Advantage+ Shopping.
You set it at 10%, and your back-end data says it’s closer to 25%. You also could have set it at 0%, and you’re seeing in third-party analytics that customers are slipping through.
Or maybe you excluded customers with a manual campaign, using a custom audience.
Yet, you know that some of the people you’ve reached are existing customers.
It’s unlikely the problem is Meta showing your ads to people they shouldn’t. It’s also difficult to prove, but there’s a much more reasonable explanation.
Possible Explanations
The exclusion is based on the custom audience or audiences that you define. These audiences are far from perfect.
Let’s assume that you used a data file custom audience of your customers. These are based on info that your customers provide. It could be just an email address or it could include more information like first name, last name, phone number, physical address, and more.
That information needs to be matched up to Facebook users. The match rate depends on plenty of factors, but it tends to be anywhere from 20 to 70%. Your customers may provide different email addresses when purchasing than they use in their profile. You also may have limited data (like only an email address) to match.
This assumes you’ve provided a file that includes all customers in the first place. You could have provided an incomplete list. If you follow Meta’s rules for custom audiences literally, you should also remove those customers who have opted out from getting your emails.
You can also use a website custom audience for purchase events. But that only goes back 180 days and it won’t include people due to iOS opt-outs and other issues. These audiences won’t be complete.
Your Goal
Your goal should be to define your customers as accurately and thoroughly as possible. Provide all custom audiences that are relevant, rather than leaning on one.
It will never be 100% complete, and that creates holes. How big those holes are will be partly up to you.
