Your platform ROAS is not the truth. It's a story your attribution tool tells you. Luke Austin, breaks down exactly how CTC approaches marketing measurement — and why the gap between platform-reported numbers and actual incremental revenue is where most brands make their worst capital allocation decisions.

This is Part 3 of the CTC Canon Series — our codified methodology across the core disciplines of ecommerce growth. In this episode, Luke covers the full measurement framework: why geo holdout tests are the gold standard, how CTC's database of hundreds of incrementality tests gives every new brand a head start, and what it means to build "progressive truth" over time instead of chasing a single source of truth.

Topics covered:

Why media efficacy is always in flux — and why any system that treats it as fixed is lying to you
The measurement gap: reality vs. fiction, and how to move closer over time
Geo holdout tests explained — how they work, why they're the gold standard
CTC's incrementality benchmarks by channel: Facebook acquisition (1.14x iROAS), Google Branded (0.27x iROAS), and more
Why Google branded search dramatically over-reports ROAS
How iROAS normalization enables true apples-to-apples channel comparison
The three-stage framework: aggregate benchmark, individual test, accumulated median
Why iROAS is always subordinate to contribution margin

Show Notes:

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