I agree completely with Ms Graham. It is passion that makes a dancer great. I would extend that to any kind of artist. Great musicians aren't great because of their technique, they are great because of their passion. The same for great singers, painters, writers, any kind of artist. Which is not to say that technique is not important, it is. But it's the passion that makes the artist stand out.
I was never by any stretch of the imagination a great musician or dancer, but I have done both. I miss both greatly and want to do both again.
I was very good at both, not great, but very good. One thing I learned has really stuck with me over the years. There were songs I knew by heart and loved to play on the piano. I practiced them over and over and over until I didn't need music. I didn't think about it. I just put my hands on the keyboard and played. It was at these times that I was my best.
The second is Polina Semionova, a ballet dancer. She is dancing to an instrumental by H. Gronemeyer. There is such beauty and grace in her dance.
Two very different dancers that evoke very different emotions. Two people who work very hard in order to dance so well. When they started dancing every bit of brain power went to learning technique. And they still think about technique, but they have mastered it. Which frees their mind to simply feel the music and pour the music and the emotions it creates within them into their movements.