Jason Fairchild is featured on ANA discussing “unified currencies”.
Unified currencies are a useful tool for upper funnel marketing tactics, but they miss the point for advertisers that are focused on bottom-of-funnel outcomes (these advertisers represent the majority of U.S. ad industry spend). The concept of outcome currencies is inherently more sophisticated than audience measurement currencies because they necessarily include drivers of outcomes, which include ads delivered to target audiences (so outcome currencies are in input to measurement currencies) — but are rarely single ad exposure events.
To learn even more about this, check out ANA’s article.