Crown
¯\_(ツ)_/¯
Tags are only a tiny factor in SEO. If it were that easy, everyone would be on the front page right? Since there are only a few limited spaces on the front page, it's logical that there must be other factors in play to help the algorithm differentiate between which videos deserve the top 10 spots. A huge factor is audience retention, for example. There's no better way in determining which videos are "good" than watch time.
I suggest you check out the SEO section for more info about it -> http://yttalk.com/forums/youtube-video-marketing-strategy-seo.88/
I suggest you check out the SEO section for more info about it -> http://yttalk.com/forums/youtube-video-marketing-strategy-seo.88/