Why brands and agencies have a much bigger measurement problem than Facebook's inflated metrics

Marketers were justifiably upset by revelations that Facebook’s video metrics had been significantly inflated by between 60% and 80%. The knock-on effect such errors have had on hundreds of millions of dollars worth of brand investment is incalculable.
But what if marketers aren’t measuring the right things in the first place, and haven’t been for a very long time? What if the Facebook error is nothing compared to the bigger picture of what marketers are missing? What if brands