Paid a visit to WDC (writing.com) today and entered my second writing contest for the year. I do it partly for the prizes and partly just to push myself as a writer. I've done well in most of them and have actually won a few. That doesn't make me an expert on any winning formula. Sometimes I'm as baffled by the results as anyone. I have learned a few things, though.
Who the judges are can make a world of difference. No matter how good your writing skills are, if a judge does not like your writing style or genre you're doomed.
My daughter has run into that once and honestly I think I had more trouble getting over the results than she did. She got a note from one of the judges telling her that they detested fantasy. There were no genre restrictions on the contest but it was very obviously the reason she didn't place. I read her entry and was intimidated out of putting in an entry myself. I also read the other entries including the eventual winners. They weren't that good. If this happens to you, don't let it bug you. It happens and rarely can you do anything about it.
The fact is everyone has different tastes. I've entered a comedy writing contest and got honourable mention. One of the winning entries was slapsticky. Some people like that and some find it stoopid. What the judges like matters. Don't let it discourage you. If your stuff is good, keep writing, your audience will eventually find you.
The other thing I learned to improve your chance of winning is to submit just a few days before the deadline. This especially helps when writing comedy pieces. My theory is that if you give the judges too long to think about it, they become less enamoured with your work with time. Don't give the entry time to get stale in the eyes of the judges or something fresher will finish ahead of you.
Entering contests is good for your writing just don't be too competitive about it. That can lead to unjustified discouragement when you should have won but didn't, being intimidated by the competition by reading what you're up against and then not bothering to try, or getting angry with the process because you feel slighted. If you want to be a better writer don't ignore entering contests, there's more to gain than the prizes.