Excerpt from this article:
The short shelf life of [Snapchat] images lets teenagers abandon the need to emulate the perfectly posed celebrity, or to represent life as more fabulous than it really is.
…Most visual platforms put feedback from peers at the center of the experience. Life on Instagram, for example, is as much about the rush of scoring likes as sharing something creative with peers. Many users view likes as a barometer of popularity and even self-worth, with some even deleting posts that haven’t drawn enough attention. For tweens and young teenagers, the yearning is so powerful that many post content designed only to collect likes (the popular “rate for a like” post, for instance, offers to rate friends on a scale in exchange for a like). They may follow “Instagram stars” with hundreds of thousands of followers, observing what appear to be perfect lives that are, in reality, perfectly curated.
Not so with Snapchat, where audience participation is minimal. There is no “like” button to be found here, and no unwritten rule of reciprocity. Users have two choices to share content: post a Story, where the app will stitch together a slide show of your content from the last 24 hours; or share directly with a person or group of your choosing. You can see who watched your Story, but viewers can’t reply. That means you spend more time sharing and consuming, and less time worrying about who liked you and who didn’t.