You shouldn't have to go back and modify a program's source-code just to find out what some part does when run. That's just plainly obvious to me as a principle

You shouldn't have to go back and modify a program's source-code just to find out what some part does when run. That's just plainly obvious to me as a principle. If we have no other option then sometimes we have to use non-ideal approaches, but I don't get the impulse to start saying that tooling/observability poverty is actually good.