To deactivate one's facebook account temporarily or permanently.
There are three main reasons why people facequit:
1. To again be the douche that flaunts the fact that they don't have a facebook account, because of their craving for perceived superiority over facebook users (95% of facequitting demographic)
2. They're conspiracy theorists/paranoid, i.e., they believe the government, aliens, your mom, or any combination thereof are using facebook as surveillance.
3. They've undergone an emotional time in their lives. Most likely, if they really are going through this, if they facequit, it's rather serious; if it's really not that bad, they will not facequit; rather they will use facebook for attention.
Joe: "I guess Dave doesn't have a facebook. Good for him, it's really unnecessary, frankly."
Bob: "He has one, he just facequit. He's doing it for attention and because it makes him feel superior. He'll be back on it in a few days at the latest."