On later, closer inspection (some of it performed by federal law enforcement), much of AOL's new advertising money was coming in based on methods that were unorthodox and unsustainable. It didn't begin that way: in the early days, Berlow and Pittman tried the traditional sales approach. As the biggest "interactive" firm they figured they might land the whales of advertising: companies like Coca-Cola, Procter & Gamble, General Motors. But there were no takers. Ad buyers at major brands can be conservative, and tend to favor established channels with well-worn metrics. And to be fair, there was at the time absolutely no empirical evidence that Internet advertising worked. As Michael Wolff wrote in the 1990s, "No products have disappeared off America's supermarket shelves because of the Internet…no commercial fads have been created, and no buying habits have shifted." AOL was well known, but it lacked the data that advertisers had grown to crave, and on the basis of which it made buys with the established attention merchants, like television networks and newspapers. Even with access to millions of minds, AOL advertising seemed to most big brands like throwing money into the vortex.

Tim Wu, The Attention Merchants, loc. 730