Yes, flexibility of body and physical perfection for Yogasana is important. However more important is the state of your mind, Meditative mind. Your flexibility might be excellent but if your mind is not attentive, you are merely doing some physical exercise, not Yoga.
Yoga allows you to rediscover a sense of wholeness in your life.
The ribs are the wings of the body. Open your wings.
The supreme adventure in a man's life is his journey back to his Creator.
When the mind is controlled and still what remains is the soul
There is no progress toward ultimate freedom without transformation, and this is the key issue in all lives.