Ask you yourself these questions; "Why do I want to do YouTube? Do I want to do it because I have a passion I want to share with others? Do I want to do it because I want to make money? Do I want to do it because I want to be famous?" The answers to these questions will be the primary deciding factor in how you go about doing YouTube.
If your reason for doing youtube is because you have a passion, then follow your passion and don't worry about subscribers or views. Youtube is a great place to follow your passion.
If your reason is to make money, then forget your passion and what you want and follow the popular trends. Find out what is the most popular type of content and figure out how to make it for yourself. You may discover that YouTube is not the best place for you to make the most money.
If you want fame, study famous internet personalities that came out of nowhere (did not have fame before starting YouTube) and try to mimic their path. Again, you may find that YouTube may not be the right place for you to find fame.