The angle that this photo is taken at completely changes the whole thing. If it was taken straight on, you wouldn't be able to see how all the diamonds are converging. Also, the way that the blue slowly fades out of the shot as you follow the diamonds up, creates a lot of depth in the photo.
There is a lot of negative space in this photo. There really isn't anything going on, which makes you focus all your attention on the cat at the doorstep. It makes the photo more mysterious and makes you wonder what the cat is looking at.
