As a partner you’re basically self-employed (not truly, but that’s the ethos).
If you’re a self-employed one-man-band, doing jobs that will always be in good supply and/or have little competition, you may be at liberty to down tools completely for however long.
If you’re self-employed in an industry where competition is fierce, or you have other partners who demand a certain revenue in order for you to remain a partner, you will almost never be able to down tools completely. Exceptions need to be extreme: marriage, birth of a child, bereavement of a close relative, hospitalization. Because if you do down tools, your partners have to pick up your slack, and why would they?
It’s a vicious, miserable, selfish, unhealthy way to work. But it’s also very personally profitable and can make a certain type of person feel good.