Mistress Roxana likes to show her slaves what it is that she wants them to learn. This is because she knows that if they witness or experience it firsthand, they will remember it than when it is only left at theory only. She wanted to toughen her slave and to make her hardworking so she rode her back like a pony and she did not allow the girl to take a rest. That was how she was to learn about toughening up and being hardworking.