Facebook is tough to quit, and investors like that

Slowing growth. A weak platform for mobile advertising. Privacy legislation that could hamstring profits. With all the negative headlines, including General Motors Co.'s decision this week to pull its Facebook ads, why is there such a frenzy to buy shares when the company begins trading May 18?

The answer can be found partly in the experience of people such as DeAnna Stephens of Charlotte (NC). The 36-year-old video producer quit using Facebook in December, deciding she was frittering away too much time reading about what her friends were eating for lunch. Then she realized that she had lost touch with 900 people. "I couldn't believe how out of the loop I was on things in life," Stephens said. Tired of being the last to hear about new jobs, new boyfriends and new babies, she signed up again "simply to be back on the radar."

Wall Street analysts and others have an array of concerns about Facebook's ability to churn the kind of profit necessary to justify its initial market value of more than $100 billion. But the consensus is that, with no competitors of its size and nearly 1 billion captive users, Facebook will somehow find a way.