That is a great quote too...and kinda goes along with what Bukowski said. The name of his poem I was talking about is "So you wanna be a writer?" This is the first stanza:
if it doesn't come bursting out of you
in spite of everything,
don't do it.
unless it comes unasked out of your
heart and your mind and your mouth
and your gut,
don't do it.
if you have to sit for hours
staring at your computer screen
or hunched over your
typewriter
searching for words,
don't do it.