The fact is, space development used to be done on a cost-plus basis (old style) and is now moving strongly to a fixed cost basis (the current facts of life).

For NASA, it is old style: why offer cost-plus contracting when companies like SpaceX are willing to accept a firm fixed price contract and actually deliver on it?

There is no way that SpaceX is making a profit on their lunar lander contract (Starship HLS). But SpaceX doesn’t care because they are betting the company on Starship and returning humans to the moon after over 50 years is an amazing opportunity to demonstrate the capabilities of their platform to the world. Boeing isn’t betting the company on a spaceship. Taking a multi-billion dollar loss on a contract today and hoping you’ll make it back somehow some years down the track is not the Boeing way - at least not nowadays

> since there were too many legal battles about fixed price not being finished according to spec.

Maybe in space it helps to have clearly defined success criteria - either it gets there and back in one piece, or it doesn’t. In software the criteria for success are often a lot less clear.