1990's C practice was to document whether initialization values were copied or adopted. I'm curious why the concept became "move" rather than "adopt", since move gives the parameter/data agency instead of giving agency to the consuming component.

I'm not sure how any notion of ownership and adoption in C would carry over to C++, since one of the problems with C is that it didn't define ownership. If you have a pointer value in C it means nothing about ownership.

Given the limits of C, "adopting" a pointer variable would just mean that the foster-parent now had a copy of the pointer, and was considered owner of it, now responsible for freeing it too presumably. It's basically a move, except the source can now mess things up by still using the adopted value after the adoption.