Pain and trouble is common to humans,
Yet the full blown miserability personality is problematic on many sides.
It means in a sense giving up on life.
It means exploitation of others.
It means reduce of self
It means bad relationships with others, as good relationships are those where each side is contributing. Being "useful for nothing" is a poor thing for productive relationships
This is the rational approach for life, i always tried to adopt. But i cannot judge poor and miserable people. My advice however, is never allow yourself take this role, it brings bad outcomes.