How the text arrives
sourcedAI explanation
With government bonds you lend money to the federal treasury and get it back with interest on the maturity date1. The bonds can also be sold before maturity, but in that case what you receive follows the market price of the day2. In practice it is like leaving a plan before the end: you do not lose your right to the money, but how much you get depends on when you leave.
The analogy is the AI's and is marked as such. You know what is a citable fact and what is teaching scaffolding.