Question

why you think artists rarely use symmetrical balance in their work

Answer 1

I think artists like to make their art with curvy lines and shapes instead of symmetry. They want people to see art that shows emotion and colour  instead of a symmetrical masterpiece.

Answer 2

Because symmetry is predictable. It's unimaginative. It's plain. It's cliched. Art is about freedom of expression, capturing the essence of the subject matter whatever that might be, it's about interpretation and creativity and emotion. Symmetrical balance is boring. Art should be convey a message about life and life is never symmetrical, life is topsy turvy, upside down and inside out.