Admirably punchy summary from Twitch founder Justin Kan of why people (especially kids) find Snapchat so liberating from the horrible competitive anxiety they feel using Instagram—what he calls “the 9th circle of hell where everyone feels inadequate”:

There’s no combined feed. If someone wants to look at your s***, they have to click on you. There’s no public view count, follower count, likes count, or any other social dick-measuring contest. You can just put whatever you’re doing on Snapchat; if people don’t like it, who gives a f***, you’ll never know.

Also, everyone sucks together:

The content doesn’t have to be that good, because “it’s going to disappear anyways, and everyone else’s content isn’t that great either.”

The genius of Instagram was in helping regular people be better.
The genius of Snapchat was in making people not care.