Why not let GOD decide?
Do you NOT think that HIS reasons might have some value?
Is this person's inability to cope with reality reason enough to die? I won't second guess our good Lord.
For all you know, consider that schizo on a traffic island with a cardboard sign. Our pumping him full of Thorazine or Lithium might be preventing a prophet from handing us a new book of Revelations.
Playing the Never Question God's Will card is right up there with the Race card.