Aesop

“ But the Ass was as discontented as ever, for he had to work harder than before: so he begged Jupiter for relief a second time, and Jupiter very obligingly arranged that he should be sold to a Tanner. But when the Ass saw what his new master’s trade was, he cried in despair, “Why wasn’t I content to serve either of my former masters, hard as I had to work and badly as I was treated? for they would have buried me decently, but now I shall come in the end to the tanning-vat.”
Servants don’t know a good master till they have served a worse. ”