tldr; money
"This basically has to do with the nature of Commercial Crew and NASA’s evaluation of risk and redundancy.
For every era of spaceflight before this current one, NASA used a different model of procuring spaceships. They laid out their exact needs, identified the contractor, and managed every stage of the spacecraft, from design to development to construction to the flights to the refits. They were deeply involved in every single thing.
They decided to try a different approach with Commercial Crew. Because it was going somewhere we were relatively comfortable with at that point — the ISS — NASA decided to basically partially fund the development of these spacecraft, but allow private companies to design and innovate, as long as the companies met NASA’s broad requirements and safety standards, as well as reach specific milestones (one of which is a successful crewed flight test.)
This also meant that NASA isn’t bearing the brunt of the cost — they paid a set fee for the development, test flight, and subsequent operational flights, and if the contractor went over budget, that was their problem not NASA’s. (Compare this to the ballooning costs of SLS, which is the Artemis rocket which will end up costing NASA an estimated $4.1 billion per launch)."
Let's talk about that "unsuited return" scenario.
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