You know it's a good story when after having read it, you feel sad for what the protagonist went through. I can also understand the mother's attempts to help her daughter (but with a wrong approach) become successful because she probably didn't want her ending up cleaning houses just like she did or maybe she wanted to make herself appear special because of her daughter's achievements.
I will keep the moral of the story just be yourself and just because you're not a prodigy doesn't mean that you're not enough. Everyone has value just for who they are :)