My first impressions of this image are, unfortunately a little bored. Don't take this too personally, this is a fine image and well taken by someone who clearly knows how to use their camera. I think the problem with your image is that the subject is lacking interest. In order to take a picture of a building and make it score highly, one needs to take it in an abstract way, even an interesting change of contrast might have brought a few more of those interesting details that most people overlook.
I think the time of day when you took the photograph could have been a little different to bring out more of the colours as well. Even though everyone likes a blue sky, this one kind of bleaches out the vibrant colours of the three spires.
However, will all that said, you should be disappointed that your picture got such a low mark. It seems as though your skill with your camera is fine with the right settings chosen to bring out the best possible photo.
As well as some perspective distortion (ie: top of building is narrower than bottom) - which I don't really mind - this image looks a little rotated. Perhaps its just the distortion tricking my eyes though. Also, a little sharpening in an image editor would really bring this shot to life.
The biggest problem I have with this photo is that is seems to lean to the bottom right. Perhaps a simple rotation counter-clockwise in photoshop to straighten things up would have helped a bit.
That's a nice looking building but your photo needs some improvements. It is tilted slightly to the right and it seems washed out. A polarizing filter would help, or adjusting the contrast.