"Systems evolve around what is easiest to explain, not what is most accurate.
Read the quote as instruction, not as comfort. In a rewrite proposal that assumes the ending is known, the word accurate is where the cost hides. If you miss it, you will pay it later.
In a rewrite proposal that assumes the ending is known, the failure mode is rarely ignorance. It is choosing as if the system were simpler than it is, then being surprised by the interaction effects. You see it in a retry policy change that turns one failure into a storm. If the exception path is informal, it becomes politics; write the signal that makes an exception legitimate and who can approve it.
James G. March is a reminder to keep it concrete. Write the hidden assumption as a sentence, then choose the signal that would break it. A clear line beats a long explanation.