SPM is just a starting point for students venturing into University. It is just an indication on how well you performed in academic at that particular point in your life. It's not something that seal your destiny on whether you will be a successful person in your future career. If someone always persevere no matter the obstacle, he/she will succeed (this include being a successful badminton player). If one gets complacent or just couldn't be bothered anymore, he/she is bound to failure. It's the attitude that determines one's success in the long run, not anything else like talent or luck factor. I know I am still not answering your question but a mere certificate can't tell you how good a person is. But her attitude and commitment level might tell you whether she will be good in the future.