How does the local news capture and hold the attention of viewers and prevent them from going to bed early?

How does the local news capture and hold the attention of viewers and prevent them from going to bed early? How do they weave in half a dozen presenters (national news, local news, weather, sports, etc.) smoothly? How do they manage to present 5-10 news stories in approximately 20 minutes? How do they use audio clips, music, on-the-street interviews, and graphics so naturally?