[bryanlarsen]

Designing the second stage first is ballsy, it means that you're dependent on someone else's first stage for launch.

But it's also brilliant. With Starship and Neutron coming on the market in the next few years, and their reusability enabling dramatic cost reductions, any launch provider in the future is going to be either fully reusable, massively government subsidized, or dead.

There are other rocket companies pursuing first stage reusability, most notably Blue Origin. To remain viable they'll either have to build a reusable second stage, partner with somebody who does, or acquire them.

Edit: I may have misread the Neutron announcement, and they haven't announced full reusability, yet. I still believe they will eventually do so, but...

[bryanlarsen]

Relativity is the other company that has recently announced they're working on fully reusable rockets.