When you photograph symmetrical subjects, like this view of the Louvre in Paris, make sure the camera is precisely dead center. This underscores the symmetry of the subject, and it makes the picture look balanced. If the camera position is even six inches off-center, the horizontal lines in the picture won't be perfectly parallel with the top and bottom of the image, and the shot will look off-kilter to a certain degree.
This picture was taken on my current photo tour of Paris and London, and I showed this particularly strong composition to several of the people traveling with me. You would be surprised how many people have a hard time finding the center point. In this case, it was easy to find because it was a simple matter of aligning the center line of the closest pyramid with the highest point of the pyramid behind it.
When shooting doors, windows, and other architectural features, shooting from the center point makes the picture look like it should.