I think two things hurt this image and one thing really really helped it.
First, this image is a FANTASTIC action shot. That is the best thing about it, and the thing you probably saw when you decided to enter it. The spray is great, the action is caught at the exact right moment.
Now, the problem is two-fold. First of all, the serendipity of the shot is missed because we don't know if you went to an event, if this is your friend, etc. This could easily be a "posed" shot (setup shot) as well as something you just walked by and had to take the pic.
Also, the image is a bit small. Size the largest side to 640 pixels and let us see the details in such a great image. Do that and you'd have a 5.5 on this shot.
Crop to make the shore line divide the image into equal halfs. The surfer, board & the curving water spray is placed precisely at the shore line interface will make the image beautifully balanced. The surf spray at the bottom distracts