In the old event-driven world, it wasn’t like that. As well as worrying about creating the views corresponding to those states, you had to consider the transitions between states — from a to b, a to c, a to d and so on — but also from b back to a, from b to c… until you end up with a combinatorial explosion of code paths. Now imagine we added a seventh state, or an eighth… and if your app only has 8 possible states then I envy you.