I think this photo is really well done. The composition is interesting and balanced, the cat is the focus, sitting confidently one third up and one third in, according to the golden ratio. It's framed in a square of grey, which mirrors the hole in the wall it seems to be watching and the tiles on the floor. The cat, in its mottled grey appearance fits in really well in its surroundings of white, grey and black, which you caught and underlined with your choice of composition.
I also love the subtle humour of the piece, a painted cat watching a hole in the wall surrounded by bird-droppings. There is a bit of red on the edges of the hole - has the cat been successful before, and maybe spilt the red paint blood of painted pigeons?