This shows up in every high-repeat category sooner or later, and sanitary pads are a clean example because people reorder within weeks. We ran into it on one account. Excluding existing buyers to chase new ones made the algorithm perform worse, not more targeted. Leaving them in fixed that, but for a reason that turned out to be its own problem.

True Omnichannel MER is Adbuffs’ measure of real efficiency — net-delivered revenue across D2C, marketplace, and quick-commerce, over fully-loaded spend.

The other 99% of your business is dark to Meta’s AI — every in-store sale, every phone order. Here’s what it cost one brand to stop feeding that signal back.