Almost all psychiatric disorders have biological-psychological-sociological basis. The best example for this classic rule is probably the obsessive compulsive disorder.
On the biological side there is the inability to divert one’s attention; on the sociological side excessive rules; on the psychological side the impulse to break rules at each given opportunity and feeling guilty as a result of it…
Can you imagine what a difficult situation this is to be in? Like a tightrope walker 50 meters above the ground. You have to adhere to rules, but you want to escape this situation instantly and you can on no account divert your attention.
After all, crashing to the ground is a terrible end. Or at least shameful!