very late into slavery times, almost near the end of the entire institution of American chattel slavery, the wealthiest of slave owners would hire their slaves out much the way they might rent an extra horse or bull to a less-endowed neighbor.
it was common, among these wealthy slave owners to allow a slave to keep the tiniest part of this payment. it was common, because it gave the slaves hope. a slave with hope would work harder, whilst a slave who was only beaten would either work less, try to revolt or run, or try to kill themselves. this was an unacceptable loss of revenue to most slave owners.
what these slaves didn’t know is that the harder they worked, the more they produced, the more they learned at these, um, off-site “jobs”, the greater their value was, and the more and the longer they’d have to work to “purchase” their freedom. in fact, some of these slave owners would change their minds altogether — without even telling the slave — and decide not to grant their freedom at all.
very few slaves earned their freedom that way.
it was a very elaborate ruse, not intended to fairly compensate, but to boost profit and production.
and in the end, for the vast majority, there was no hope of freedom. for hundreds of thousands — for millions — there was never any freedom at all.