In 2008 Yahoo made a bid to buy Facebook for $1 billion. At the time, Facebook's lead investor, Accel Partners, told a 22-year-old Zuckerberg to accept the offer and to sell to Yahoo for $1 billion. But the well known investor Marc Andreessen urged Zuckerberg not to sell.
"Every single person involved in Facebook wanted Mark to take the Yahoo offer," Andreessen recalled. "The psychological pressure they put on this 22-year-old was intense. Mark and I really bonded in that period, because I told him, 'Don't sell, don't sell, don't sell!'"
After Zuckerberg turned down the bid from Yahoo, he explained his decision that he couldn't imagine himself doing anything else than building a social network. if Zuckerberg had not founded the social network Facebook he would probably have founded another one. Something like FaceMagzine or PeopleNet or HeadList or...