Another brief takeaway for me was that businesses that grow quickly either 1. see an extremely reliable 4x return on advertising expenditure Or 2. do not hav

Another brief takeaway for me was that businesses that grow quickly either 1. see an extremely reliable 4x return on advertising expenditure Or 2. do not have advertising expenditures at all. One caveat to the article is that it is not in every business's long term interest to grow quickly.