What is the difference between symmetry and approximate symmetry?

Symmetry can be very stiff and formal, identical. Approximate symmetry has the stability of formal balance, slack differences in their size.

Symmetry appeals to us, but it can be stiff and formal. Many artists avoid boring the viewer by adding small differences, creating approximate symmetry ... Rather than consisting of halves or sides, it relies on the artistic arrangement of object to appear balanced. "asymmetry" involves a balance of unlike objects.