Talking from experience I find that when my mistress wanted to humiliate me she would do it in such a way that I would not feel more exposed and vulnerable than ever but also more turned on than ever too. She would seduce me for what seemed like an eternity then get me play with her in return and after she had come, I was alowed to masturbate infront of her whilst she used her Hitachi Magic wand. This may not sound too bad but being in front of your mistress using a magic wand and wanting some contact more than ever is unbearable. Looking at her as she had yet another orgasm.
Then again she would tell me to ask permission to come then deny my request so as I was forced to stop at the very edge.
So in respect to the question I think physical and verbal humilition are tools used in an alarmingly effective way.