I like looking for interesting patterns, textures, lines, shapes, and colors in images. These graphic elements can add a lot of interest to photos or can just as capably function as the subject.
This photo has a little bit of everything. I love the four rectangles of color, and how each one has left a different trail below it, the black rusting the metal underneath, and the red streaking all the way out of the photo.
I also love the texture of the old weathered materials, corrugated metal panels and faded wood doors. Last I like the shapes. These seemingly unrelated elements all combine to make an interesting abstract from a real object.
The last aspect of this photo that draws me in is the oddity in the painted rectangles. I can't quite figure out why they are there.