But if you hurry up and figure out that you made the wrong decision and you have the agility to then say, okay, that was not right, let's try something else, then. It works. At NASA, we had all these contractors and suppliers and a very cumbersome kind of system that we took a long time to make sure we made the right decision, because changing things was prohibitively costly. But SpaceX doesn't have to worry about that now.