What is the Future of Youtube?

What is the future of Youtube shows?

Youtube and by default all of its hit channels are less than ten years old, but let's talk about how time affects Youtube. We've already seen the top channels peak and descend. The crown for most subscribed channel went from Ray William Johnson to Smosh to Pewdiepie. The crown for most watched recently from Machinima to Rihanna. Some Youtubers have made the transition to other media, or are trying to, like Toby Turner and the Fine Bros.
But I'm wondering if the future YT channels will be like other media or not. What will happen whenever someone wants to end their channel or a member of a duo wants to leave and the other wants to stay? Will Youtube channels die like cancelled television shows? Viewers are not as accustomed to endings like that online as on TV. How will audiences respond? If one of the Fine Brothers or Smosh guys wants to move on to something else, will the show continue with a new person like a late night talk show or SNL? Or are YT channels and their viewership not built to outlast their creators?