diff --git a/trace/trace.go b/trace/trace.go
index 4ff03e86d52..1b5ffb00a1f 100644
--- a/trace/trace.go
+++ b/trace/trace.go
@@ -364,8 +364,9 @@ type Span interface {
 	SpanContext() SpanContext
 
 	// SetStatus sets the status of the Span in the form of a code and a
-	// description. The description is only included in a status when the code
-	// is for an error.
+	// description, provided the status hasn't already been set to a higher
+        // value before (OK > Error > Unset). The description is only included in a
+        // status when the code is for an error.
 	SetStatus(code codes.Code, description string)
 
 	// SetName sets the Span name.