Why intent pools are the hidden key to understanding Facebook

The idea behind Facebook Lookalike Audiences is simple: upload a list of customers and let Facebook find more people likely to buy.
Each Lookalike Audience is available in a range from 1% to 10%. This describes what percentage of the population is being matched. For instance, a 1% Lookalike Audience in the US targeting the 1% of the US population that looks the 'most' like the seed list. In theory, as you increase your percentage, the similarity with the seed group declines and, with it, similar