Hi Asher,
The first two which you pointed out are actually taken from an angle which is right of center. Its not as dramatic as the two of the buildings that contain the cloudy blue skies but it is an angle. The other two are clearly taken from an angle which is left of center. The image of the factory was taken from what I consider to be the front. The left edge of the building on the right side of the image is actually in the center of the composition. The angles from which these images were taken are deliberate in the sense that they provided the best composition which I could find. Particularly they were the most harmonious compositions which were "available". Certainly a better composition could be wished for, but these were the best angles I could find within a reasonable time frame.