you can’t push and write at the same time

In All the Great Writers, Charles Bukowski describes a conversation between a writer, James Burkett, and publisher, Henry Mason.

“look, Burkett, you’re a pusher. as a pusher, you’re great. why don’t you sell mops or insurance or something?”
“what’s wrong with my writing?”
“you can’t push and write at the same time. only Hemingway was able to do that, and then even he forgot how to write.”

(From The Most Beautiful Woman in Town & Other Stories)