“Take a human desire,” says Twitter co-founder Evan Williams, “preferably one that has been around for a really long time…Identify that desire and use modern technology to take out steps.”

It’s interesting to think about this as Instagram’s identity has evolved in a “lol nothing matters” Snapchat world. (I initially typed “Snapshat”; Freudian?). Founder Kevin Systrom used to like to describe the product as “a visual walkie talkie,” but plainly that wasn’t true. As their head of product Kevin Weil said, “It became a place where people kept raising the bar on themselves in terms of the quality of what they had to achieve to post. We didn’t want that.” If you haven’t yet, listen to the This American Life episode about teenage girls’ Instagram anxiety referenced in “The Instagram lobster trap.”

Anyway, Instagram has found that lowering the bar—creating an impermanent, low-stress complement to one’s highlight reel—is key. They need bottom-up activity to make things work:

“Your connections with your friends and your family are the thing that make Instagram work. All the data supports that if you follow more friends and engage with your friends, your activity goes through the roof. If you just follow more celebrity content or more interest-based content, that doesn’t move the needle at all.” – Kevin Systrom, Instagram co-founder

You should read Benedict Evans’s observations (starts dry, but solid) about all this. Among them:

There are millions of people who will post beautiful pictures of coffee or 1960s office blocks, or like a photo by a celebrity, but there are billions who’ll share a snapshot of their lunch, beer, dog or child. Instagram is moving to capture that in the same way Messenger and WhatsApp captured chat.

Seriously, it’s worth the read.