We know that social media isn’t great for our mental health—plenty of studies have found correlations between heavier Facebook use and depression, feelings of envy and isolation and lower self-esteem. Now, a study finds that after a week of quitting Facebook, people’s mental health is considerably improved, and their feelings of envy somewhat dissipated. It seems like enough studies have found that social media is detrimental to our well being—so why can’t we stop ourselves? Part of the reason may due to a fundamental and deceptive disconnect between what we expect from Facebook, and what we actually get out of it.