Writing contests are crap shoots. Just because you don’t win doesn’t mean your work sucks. First of all, the more entries there are, the stiffer your competition is. Your story can still be great but loose because others stories were simply greater.
There is also the problem of the specific tastes of the judges themselves. I don’t care how unbiased they try to be, they still have their preferences to what they do and do not like. And if you’re not what they like? Well, the odds are stacked against you even further.
Then there are other factors to consider too. Are the winners being compiled into an anthology? What if you have written a kick ass paranormal romance but so did three other authors? What if yours and these other three were the best four stories in the entire competition? What if the judges decided they only want to have one such story in the anthology to keep the selection broad? Well, you can’t help that.
There are just so many factors beyond your control. The best thing to do is just submit your best work. Don’t try and figure out what the judges want. Don’t try to outguess the competition. Just write your story and submit it. Don’t take not winning too hard as long as you submitted a top notch story.