Joshua has a YouTube channel he's proud of, but he's not happy with his view counts. Leo says that view counts can lag behind on YouTube if they come in too fast. If he's actually talking about overall subscriptions and viewership, there's a misconception due to the success of videos that go viral. Viral views are an unrealistic barometer. Leo also says that we overestimate the value of a YouTube view because we don't know how YouTube counts views or how often a video is viewed multiple times. How could he make it go viral? Humor is a good method.
Markus Brownley (MKBHD on YouTube) is a great example of how to build an audience, as is PewDeePie. It really comes down to content. Great content is half the battle, then he has to get the word out. Social media can help, as would crossovers with other YouTube stars who can introduce him to a new audience. If he can create great content, in the end he'll win.
There's a great article about chasing YouTube success in the New York Times. It's hard work, and frankly, Leo isn't much of a fan of the YouTube model.
Check out Joshua's YouTube site here: http://www.youtube.com/thejoshuaplays