"i could say the world is unfair for having such a beautiful person being so talented as well, but there is only one truth: this girl practiced a lot to be this good,and so should other people too." (One of the comments on one of her videos) And then there are people in wheelchairs. There is no bigger proof that this world is not the main world, and you are only preparing for the next world by doing G-d's commandments regardless of what life throws at you.