If you're new to the site, and you post directly to the wiki without first taking advantage of the many tools we have here to help people become successful authors, then yes, very often the result is a large number of downvotes and eventual deletion. That's usually because some error has been made: poor spelling and grammar, poor narrative, not keeping with SCP's tropes, accidentally or purposefully copying something that's already been done, all that.
However, we'd be more than happy to help you make your new article as good as it can be, before you post to the wiki. First, read over How to Write an SCP. There's a lot of good information that will help you avoid common pitfalls (and yes, they're common, that's why the downvotes are normal).
Then, get yourself a sandbox and write up your idea there. Now, once it's up there, you won't get feedback until you ask for it. Use the Draft Forum and the Chat to meet with people and get feedback on your ideas. Take the feedback to heart; it can mean the difference between a good and a bad article.
Once you've got your sandbox article to a point that people think it's going to survive, then post. There are no guarantees, but this will much more consistently get you a better article than just posting it cold.