I don't think that's quite it - review is a recurring cost which you pay on every new PR, whereas writing code is a cost you pay once.

If you are continually accumulating technical debt due to an over-enthusiastic junior developer (or agent) churning out a lot of poorly-conceived code, then the recurring costs will sink you in the long run

"review is a recurring cost which you pay on every new PR, whereas writing code is a cost you pay once."

Huh ? Every new PR is new code which is a new cost ?

> Every new PR is new code which is a new cost ?

Every new PR interacts with existing code, and the complexity of those interactions increases steadily over time