I think the problem is that social media usage is on a continuum, and you can find yourself at a local maximum that is well below your global maximum. For example, if you check FB once a day, then maybe you would be somewhat happier if you increased to 2x or 3x daily. But if you decreased your usage to once weekly, then you'd actually be much happier. The problem is that you'd have to go through the "valley" of once every 3 days and once very 5 days before you get to once a week. There's also the fact that FB sets up the bday posting stuff to encourage you to log on every day.

I wish there were ways to distinguish between periodically checking FB and essentially being addicted to it (several times daily use). Perhaps we could employ language like "I use FB" versus "FB uses me". Only half-joking...