Facebook is vanity. It is really all about ego. People love to stroke their ego. It is hilarious to me how many will defend pride and how many somehow confuse pride with virtue, when the opposite of pride, humility, is the virtue. What made Facebook popular is the same thing that makes any vice popular, such as gambling or drinking, because pride is a vice, also known as an indulgence, and pride, ego, and vanity are definitely not virtues. Facebook (and, to similar extent, Twitter) has tricked its users into believing that vice and indulgence are virtuous, and excessive vice and excessive indulgence are most virtuous. But we all used to know that excessive vanity and excessive pride, or hubris, is counted among the seven deadly sins. Facebook is basically a mass-vehicle for sin, and sin, as a transgression of divine law, feels really great. And that is how Facebook (and Twitter) did it, by presenting opportunity to violate the First Commandment and make everyone worship themselves and think they're God, at least while they're logged-in.
Oh, that's not what got Facebook big. You can stroke your ego in emails or blogs or on forums.
What made Facebook great was that it encouraged users to share personal information (including pictures and bio items) and then made it easy for everyone to anonymously take part of this information.
You could look at pictures of your crush in cute outfits or co-workers in embarrassing situations. You could read about the layoff your ex' new partner had to endure. You could see where the cool kids had their coffee. All of this at any time of day, and nobody but you would know that you knew.
It's the ultimate low-key stalking tool and it was designed this way from the start, because early on they understood that's what people want.
I don't remember the exact quote but I do know one of the early decisions was that photos ought to be open by default and you shouldn't be able to tell who has looked at them -- in contrast to many other social networks at the time.
Voyeurism, mixed with a little FOMO - they had a limited release early on, just like GMail.
I think a large part of it was also the digital photo and smartphone revolution. Instagram did that a little better, but posting straight to Facebook was a little better than what... Photobucket? Personal hosting? Emails with mass CC? It just solved that problem so well for not only the big event pictures we'd traditionally throw in an album, but also adhoc slice-of-life moments.
It also gave that power to businesses, humanising them in a way that hadn't been possible before, and that's where the money came in.
> it encouraged users to share personal information (including pictures and bio items)
Yes, precisely. This is my point entirely, that ego, vanity, pride, conceit and narcissism is what motivates these individuals to want and need to share personal details with complete strangers, and this is the entire point of Facebook, to beguile its members with a platform of opportunity to indulge in symptoms of personality disorder and character flaw.
