The Treasury's job is to finance the government's deficit at the lowest cost for taxpayers, but this is complicated by the fact that its actions change market pricing and microstructure, making cost unknowable ex ante.
Amar Raganti explains that Treasury's stated goal is minimizing taxpayer cost, but the reflexive nature of its own actions on the market makes this unknowable in advance, similar to the Heisenberg uncertainty principle.
transcript
Amar Raganti: In sort of bold headlines, the Office of Debt Management would say its job is to finance the government's deficit at the lowest cost for taxpayers. The problem, of course, is that there's a lot of things behind that. The implications go beyond just sort of what you'd call a number that you could scratch down on a piece of paper. And then additionally, you know, what you're trying to solve for is something that you won't know ex ante, meaning like you won't know as you're doing it.
explains mechanism · 1