TEAM: Your supporting cast will change over time. But when a lead/founder leaves, things are going to be very different. In the case of a single lead, the show is basically over (Kiefer Sutherland in 24). With multiple leads the show may go on but it will never be the same (Steve Carrell in The Office).
MARKET: Small ideas will not garner much interest. You have to have a story line that will last 5+ years and innovate throughout to stay relevant. The core premise needs to be big enough to carry multiple story lines, the team, too.
EPISODES: A consistent upward trajectory is unlikely (and boring). There will be ups and downs. There will be emotional moments. Take as much ownership for wins as the losses.