When she was little, Jing-mei was adamant about asserting her right to fall short of expectations and just be who she was. We call this method "shooting yourself in the foot." Jing-mei herself admitted that she might have become a decent pianist if she had tried. But instead, she tried very hard not to be a good pianist. And hey, she succeeded.
Out of all the daughters, we would actually argue that Jing-mei develops the least personally. You get the sense that she feels ungrounded, unsure of who she is, where she comes from, and unsure of her personal value. She gets her feelings hurt easily, and has a strong tendency to think that she can only be what she is today, nothing better.
Jing-mei didn’t grow up with any siblings, but lives under her mother’s shadow. Her mother, Suyuan, is extremely capable and driven, and also a great cook and mah jong player. When Suyuan dies, Jing-mei all of a sudden has to fill her shoes, not only by replacing her at the Joy Luck Club, but by stepping up to fulfill her mother’s greatest wish: to meet Suyuan’s twin daughters and tell them about Suyuan’s life. Much of this book is about Jing-mei’s path toward discovering her mother and discovering herself at the same time.
Jing-mei has a rocky relationship with her mother. She originally sees Suyuan as a hyper-critical and demanding Chinese mom with too strong an opinion of who her daughter should be. Jing-mei always feels that she is disappointing her mother’s high expectations and that her mom refuses to see her for who she is.
Through reflecting on her mother and visiting China, Jing-mei’s comes to the realization that her mother does love her. An important moment is after the New Year’s dinner when Jing-mei takes the bad crab for herself and also gets totally belittled by Waverly. Throughout this episode it’s clear that Jing-mei doesn’t know how to recognize which are the best quality crabs. Part of the point here is that Jing-mei doesn’t recognize "best quality" – she doesn’t even recognize quality in herself, always comparing herself to Waverly and thinking she’s coming up short. Suyuan gives Jing-mei her green jade pendant, calling it Jing-mei’s "life importance." Suyuan tells her daughter that the Jade isn’t good quality, but it will improve with time. Jing-mei is like this young jade, improving and deepening over time. (For more on the jade pendant, see "Symbols, Imagery, Allegory.")
Jing-mei has a lot to live up to, although she doesn’t know it until after Suyuan dies. Jing-mei’s name has two parts, "Jing" meaning the best quality or essence of something, and "mei" means little sister. Basically she was named to be the younger sister who was supposed to be the essence of her older, lost twin sisters. The whole process of meeting her sisters helps Jing-mei come to peace with her mom. Moreover, when she meets her sisters and fulfills her mother’s "long-cherished wish," she sees that between herself and her sisters, they are very much like Suyuan.