By being rough on me and helping me see that this is unpleasant and counterproductive to learning then mutual benefit again occurs.
If I have an aggressive personality and am rough on my training partners then there will very likely be someone much better than me in the dojo. By being rough on me and helping me see that this is unpleasant and counterproductive to learning then mutual benefit again occurs. I change my behaviour, and become a helpful addition to my dojo. The wider implications to culture are easy to see here.