Rilke wrote in his book Letters to a Young Poet
"... all progress must come from deep within and cannot be pressed or hurried by anything. Everything is gestation and then bringing forth. To let each impression and each germ of a feeling come to completion, wholly in itself, in the dark, in the inexpressible, the unconscious, beyond the reach of one's own intelligence, and await with deep humility and patience that birth-hour of a new clarity: that alone is living the artist's life: in understanding as in creating.
"There is here no measuring with time, no year matters, and ten years are nothing. Being an artist means, not reckoning and counting, but ripening like the tree does not force its sap and stands confident in the storms of spring without the fear that after them may come no summer. It does come. But it comes only to the patient, who are there as though eternity lay before them, so unconcernedly still and wide. I learn it daily, learn it with pain to which I am grateful: patience is everything."