a keen grasp of the obvious

Submitted by mivox on 24 April, 2006 - 3:34pm.

A 33-year-old Oregon man on methamphetamine and suffering from mental health problems fired 12 nails from a nail gun into his head and survived.
[...]
Doctors were surprised when they took X-rays and found the nails - six clustered between his right eye and ear, two below his right ear and four on the left side of his head.
[...]
Psychological examinations showed he had "poor judgment and insight."

OK people, someone kindly explain to me why a psychological evaluation was needed to determine this man had "poor judgement"? I mean, if they came up with a specific diagnosis of a specific treatable mental illness, great. But "poor judgement"??? Christ.