While the safeguards in AdWords would keep Google's core product uncompromised for the time being, corporate life is long, and shareholder demand for growth unremitting. In Wall Street's view, even the most robust advertising revenues always have room for improvement. In time, this reality would put pressure on the original bargain that Google struck with the public. Even if AdWords was a paradigm shift, it was still advertising, and Google, however ingenious, was still an attention merchant. It would, henceforth, always be serving two masters, beauty and the beast.

Tim Wu, The Attention Merchants, loc. 893