|I promised to come and comment on your image (in the scores thread), so here I am :) I am in "critique mode," so please don't take anything I write as being overly critical; they are just my observations and opinion, and I am being intentionally critical (much more so than I might normally be) so that it is hopefully helpful!
Okay, initially, the focus on this is very, very soft, and much of the image actually looks out of focus. This is possibly the biggest issue voters had with the shot. DPC voters like sharp, crisp focus. If you look at the winners in any challenge, they are all sharp without being too sharp; it's one of the hallmarks of a winning shot here. You would probably have needed to use a higher aperture to bring more of the shot into focus and avoid the overall soft appearance you have here. There should be a way to do that with your camera (it might require you shooting in landscape mode or something similar, or you might be able to manually choose the aperture).
It also appears this is a "setup" shot, that is, something you've specifically put together for the challenge and photographed. Because there are so many excellent photographers on DPC with advanced photographic studios and lighting, setup shots generally need to be near perfect technically. They need to be very well composed, focused, and well lit. I tend not to do setup shots because they are so competitive. Here, the focus issues come up again, and while the mirrors are present, the composition/crop of the shot minimizes them to a certain degree. The colors, while bright, are not really vibrant. Some work in processing to add saturation or play with curves/contrast might give the image more impact.
I hope these two points help you see some of what I saw in your image (and maybe what some other voters might have seen). You have a good eye for what is visually interesting, and with some more attention to how you shoot and processing for impact after, your scores will steadily improve here. Good luck!