A square on its diagonal becomes a lozenge shape that creates a more dynamic  composition as it introduces an element of instability. This dynamic is increased as the shutter is  marginalised to the left corner as attention is focused on its cast shadow and the right-hand side is simply white, resulting in a cantilevered composition.
NH477 ‘Shadows 8 - Yellow Shutter’ 26 x 26 inches   66 x 66 cm   [Diagonal = 37 inches  94 cm]   Acrylic on Canvas    2016