I am slowly working my way back through Henry Copeland's list of principles that make aikido go. The third one is, "Transcend victory and defeat." You have to transcend victory and defeat to the point that you stop playing dominance games with your training partners..
I had an instructor for a while some years back. Quite skilled at karate, and a great teacher. But we got to discussing aikido and judo one time and she told me that she hated those arts because she just couldn't stand that un-balanced, out-of-control feeling that goes along with practicing that material. She was self-limiting. I know I've learned a whole lot more about karate since I've been studying aikido and judo than I ever did in the years I studied with her - and I think a large part of that is because I gave myself to that un-balanced, out-of-control methodology, which allowed me to learn a lot about life on the edge of failure and a lot about getting myself out of bad situations. Because I was able to transcend that control thing, I'm still practicing and learning. (Partly) because she was not able to transcend, she's not.
This point on Henry's list also brings to mind one of my very first blog posts - the one about Productive newaza randori. See, if you fight a huge, terrible fight during every encounter that you have with a partner, then you exhaust yourself and waste all of your class time before you can get the number of repetitions that you need to get better. You have to transcend that desire to fight with your partners and get to the point that you can roll with them. When you do, you will find that your skill progression skyrockets because you are getting immensely more reps in much more varied situations.