I don't get lip-syncing part of it. Their website says it's "musical.ly is a social media platform for creating and sharing short videos." I think this abstract

I don't get lip-syncing part of it. Their website says it's "musical.ly is a social media platform for creating and sharing short videos." I think this abstract "short" word explains a lot: Youtube videos lose a lot of views, because Youtube tells how long they are. Impatient kids are like "Nah, it's too long". But by promising the videos are short, you can probably make viewers to spend even more time with an app, watching many shorter videos instead of a long one. No data to prove it, just gut feeling.