[TeMPOraL]

> if you go deep enough and talk to the people responsible for these budgets, they aren’t stupid and what they are doing is very much scrutinized

In my experience, it's not that they're stupid - but they have neither the required math skills, nor the visibility into the whole pipeline, to be able to correctly evaluate the RoI, so they trust their providers in the ad industry a lot. So the correctness of their calculations depends a lot on the virtue and honesty of people working in the industry specializing in lies and manipulation when placed in front of an easy opportunity to make extra profit by being dishonest.