This article is from the Stand-up Comedy FAQ, by Steven Rosenthal and Steve Silberberg (firstname.lastname@example.org) with numerous contributions by others.
A. Most, if not all, of the comics here are not quite as busy or successful
as they would like to be. Most will take responsibility for their lives,
and are doing what they can to be as successful as they can be. They look
to the future, and the present is seen as a stepping stone.
There are some other whiners, however, who just get angry. They want to
blame everyone but themselves for whatever has gone wrong in their lives.
Instead of trying to make things better, they run around complaining that
things aren't better.
The first group are, to me, a joy to interact with, even when things are
not going well or I don't agree with them. Even at their lowest they have a
spark of optimism that can't be missed, a knowledge that where there's
life, there's hope.
The second group, however, are a pain, and I would prefer to do without