One I've liked for a long time:

As the poems go

as the poems go into the thousands you
realize that you've created very
little.

it comes down to the rain, the sunlight,
the traffic, the nights and the days of the
years, the faces.

leaving this will be easier than living
it.
typing one more line now as
a man plays a piano through the radio,
the best writers have said very
little
and the worst,
far too much.

Charles Bukowski (RIP)