What makes someone qualify as crazy?

Question

What makes someone qualify as crazy?

Answer 1

it could mean they're insane

Answer 2

Insanity is relative.

Answer 3

Crazy is synonymous with irrational.  We don't make sense.  We may be delusional: see, hear, smell things that aren't there.  We may have exteme thoughts of paranoia, fear, impending doom.  In all cases crazy is only a problem if it interferes with a normal, healthy life.

Crazy also means passionate or fervent.  You can be crazy about cheesecake.  It may not be rational; it may not be the healthiest thing; but it's basically compatible with normal, daily living.