In this episode, Lucas and Luna dig into a performance-marketing blind spot that quietly inflates reported return on ad spend: audience overlap between ad sets. Using a concrete DTC skincare example, they show how overlapping targeting can double-count the same purchase across two ad sets, making ROAS look 40 percent better than it actually is. They walk through how TikTok's ad delivery works, why the platform doesn't always deduplicate conversions the way you'd hope, and what a simple exclusion strategy can do to clean up the numbers. Along the way, they touch on frequency capping, campaign structure, and the difference between platform-reported ROAS and true incrementality. If you're running TikTok Shop ads with multiple ad sets targeting similar audiences, this episode is a practical guide to spotting the overlap before it skews your budget decisions.