Success tells you what you already know and how far we have come.
Failure tells you what you have yet to learn and how far we have yet to go..
IMHO, they are equally important.
The discipline to train is how we discover both.
Perfectly said. I've not really been doing Aikido long enough to comment on that side, so I shan't.
However, I am a big believer in life long learning, I am a believer that every situation brings a chance to learn something new, about the world, yourself, your friends, your opinions, the universe as a whole.
In learning, you need both. Success to confirm your doing it right, to see your progress, and simply for positive reinforcement. Failure to teach you humility, to see further avenues to learn, and as you said, to see where you have yet to go.
In my opinion, you do not learn from constant failure, I know you should leave your ego off the mat, but its very much a trueism in my experience that constant failure serves to reinforce negative self image, which is in and of itself a barrier to learning.
Its also my belief that constant success is a barrier to learning. Firstly, it means you are not being challenged, this induces boredom, which, much like negative self image, is a barrier to learning. Not only does it produce boredom, but can also inflate the ego, producing arrogance, which is a barrier to learning through the belief that "you know better".
I think to truelly learn you need enough success to know your progressing, and enough failure to know you have things to still learn. Never enough success to breed arrogance or boredom, never enough failure to create negative self image. You must also be careful not to overwhelm. "I still have things to learn" can easily become the learner staring at a great mountain, unable to climb through fear of falling.
Ofcourse, without Discipline and Motivation, all of this falls by the way side, and even the right balance will fail to teach. I would also wonder whether desire should be factored in. Without desire, much more discipline is required?
Anyway, thats my $0.02.