Deleting my own entry

I just have one burning question—why on earth is such a simple feature like deleting your own entry not available? Why do we need to go through an admin just to remove something we submitted? Sites like 99Designs, your biggest contest-based competitor, let users do this easily. So I’m genuinely curious… why is this missing here? What am I not seeing? What’s the real reason behind it? Someone please shed some light; I really want to understand!