Were you really trying for a brown. If so, I'm embarrassed to say I like this :(
If not, perhaps it got punished for being abstract, or perhaps too many people looked for "something" besides color in the shot. But the beautiful continuous tones and combinations in the color are very nice. Perhaps a crop on the left to making it close to square, with the two colors playing against each other and combining in the bottom right quadrant might have been a bit compositionally stronger. (Still may not have done well in this crowd, but a good pic anyway.)
Foe me, this photo actually reminds me of some type of graphic gradation background that would be used in a psychedellic poster or graphic arts brochure. There really is not focal point for me, and so I have given this a low score.