According to Carl Jung, what does becoming conscious of one's shadow mean?

Acknowledging one's dark side and imperfections

Famous analytical psychologist Carl Jung has quite remarkably said, “How can I be substantial without casting a shadow? I must have a dark side, too, if I am to be whole and by becoming conscious of my shadow, I remember once more that I am a human being like any other”.

Carl Jung's statement suggests that to be a complete and whole human being, one must acknowledge and become conscious of their darker aspects and imperfections.