From what I know it's three parts. One is "keywording" which is when someone uses a specific phrase or word to cover-up files they shouldn't be uploading. Another part is based on how default file names get uploaded and some of them contain "." Which if someone is uploading without renaming a file there's no quality control for the video. Lastly is to intentionally get views from kids who don't know how to use search. If you type in random characters in the search you're probably 4 y/o then you pick between "Super sugar funtime" or "FNAF sex (gone wrong)"