diff --git a/docs/why-gates-are-code.md b/docs/why-gates-are-code.md
index 91f8fc5..eec09b1 100644
--- a/docs/why-gates-are-code.md
+++ b/docs/why-gates-are-code.md
@@ -55,3 +55,12 @@ to feel routine.
 That's the deeper reason these numbers live in a tool rather than in prose: prose is read once
 and remembered loosely, but a threshold enforced every call is tested by every call, and a
 threshold that fails its own test gets noticed and re-measured rather than quietly ignored.
+
+The suite's coverage floor is the same argument run forwards instead of backwards. The ceiling
+above was wrong first and measured afterwards; the floor was withheld on purpose until the number
+existed - measured, then watched across 38 runs while the code grew by a quarter, and only then
+written down as 85 against an observed 87.0%. The two points of daylight are the same
+consideration as the ceiling's headroom: a limit the ordinary case keeps tripping stops being a
+limit. A coverage floor set at the measured number goes red on the next thin command wrapper,
+which is not a regression, and a threshold that goes red for a non-reason gets lowered rather
+than earned - the failure mode above, reached from the other direction.