Another great reply, let me respond. I think there's a difference between lean and agile development. Lean startup essentially means testing and learning from

Another great reply, let me respond. I think there's a difference between lean and agile development. Lean startup essentially means testing and learning from a basic prototype for everything that you do. New feature? Test it. New level? Test it. Agile development, to the best of my knowledge (I am not a programmer), is focused more on being adaptable and changing course quickly. Lean startup is focused more on using scientific method to determine decisions rather than indiscriminate opinions of the internal team. It includes agile development but is not agile for the sake of being fast. I agree with your point that games HAVE to be finished on release. My counter to the prototype argument would be that you can launch the game as a MVG in an unbranded, low-fi way that wouldn't jeopardize your actual game's launch. Instead, you'd just have a crappy game that people would test, and then you'd kill it and launch the new game without any association to the test game at all.