A dominant sets rules which the submissive is expected to obey.
When rules of expected behaviour are broken, punishment is often used as a means discipline...
Today is an example of that... holding her hands up high whilst adding pressure to her back with heels...
Tying her legs with straps and belts so she cannot escape... adding the gag and blindfold so she can no longer see of speak...
All she can do is take her punishment and learn from it...