Why Galadriel left Valinor?

[Olmer]

According to Tolkien, Galadriel had her own plans for Endor long before the revolt of Feanor. And, seems, her plans were very well accepted and approved by Valar.
"She did indeed wish to depart from Valinor and to go into the wide world of Middle-earth for the exercise of her talents; for "being brilliant in mind and swift in action she had early absorbed all of what she was capable of the teaching which the Valar thought fit to give the Eldar," and she felt confined in the tutelage of Aman. This desire of Galadriel's was, it seems, known to Manwё, and he had not forbidden her; but nor had she been given formal leave to depart. " ("UT")
So, the desire "to rule there a realm at her own will" (The Sillmarillion) was only her private reason.
What reason she gave to Valar to be singled out to leave Valinor with their blessing?
Your thoughts?