Roger McNamee, very early investor in both Google and Facebook (and, though he's profited, he regrets it):
The people at Facebook and Google believe that giving consumers more of what they want and like is worthy of praise, not criticism. What they fail to recognize is that their products are not making consumers happier or more successful. Like gambling, nicotine, alcohol or heroin, Facebook and Google — most importantly through its YouTube subsidiary — produce short-term happiness with serious negative consequences in the long term. Users fail to recognize the warning signs of addiction until it is too late. There are only 24 hours in a day, and technology companies are making a play for all them. The CEO of Netflix recently noted that his company’s primary competitor is sleep.