This. There are two advertising business models: 1. Pay for ads to drive customers to your business selling widgets. 2. Sell customer data to advertising netw

This. There are two advertising business models: 1. Pay for ads to drive customers to your business selling widgets. 2. Sell customer data to advertising networks. The first is sustainable and is the foundation of all advertising. The second is only sustainable if it doesn't supplant the first. If it does so, it becomes a self-licking ice cream cone and the whole enterprise falls apart. Sadly, that's where we are today.