Why has Facebook flourished?

Have you ever asked yourself that question? I did.
One of the simplest explanations I have found so far comes from Ivor Tossell, a columnist for The Globe and Mail:

“The simple fact is that – like an airline or a cable company – Facebook is useful.

Every moral panic about the nature of friendship and the loss of privacy distracts from the real reason Facebook persists. It’s not that Facebook founder Mark Zuckerberg owns the social graph – the master list of who’s friends with whom. It’s that he owns the phone book.

It’s not flashy, but Facebook is succeeding at being precisely what it says it is – a face book, a directory of people, a social utility that people can use to look each other up. It came along at just the right time, and has benefited from the decline of the traditional phone book, and the rise of cellphones, whose numbers aren’t publicly listed.” (You can read the whole article here.)

Parting suggestion: Be clear about whose problem you’re solving and how.