composition
is the arrangement of visual elements in a work of art, as distinct from the subject.
The box on the far left in each row is an extremely reduced version of the images in the other columns on that same row. This reduction of the formal elements in the frame is similar to how you might choose something to watch on Netflix. The categories are simplified, dynamic (action), static (drama), ominous (horror), uplifting (comedy) or any number of other things. The formal parts and pieces at work are the same whether you are making a painting, photo or film.
Diagonal compositions are dynamic, meaning they imply movement. Imagine a ball at the top of a ramp. Now imagine that same ball on a table. If you were going to draw both scenarios for a game of Pictionary what would they look like? Because one has physical movement potential if looks/feels more dynamic. Except for the first picture, there is not a lot of movement any of the examples below which may be why the diagonal was used, adding some life to the image?
Below are examples of how complex pictures can be broken down into simplified geometric shapes and arranged compositionally. Notice how the triangles draw you in and the squares create a barrier. Circles or rounded forms imply movement and life. Adding variety of shapes to a picture creates visual interest and stability. Shapes can also be used to deepen the meaning of an image. More on that topic here.