“You could’t polish shit” is a popular aphorism roughly comparable to "Placing Lipstick with a pig" (Though "a turd" is much more commonly utilized). Even so, the Tv set clearly show Mythbusters showed that someone can, in actual fact, polish a turd. It could also refer to getting fired https://zandernvemt.blogdun.com/37921558/dyke-no-further-a-mystery