diff --git a/lisp/menu-bar.el b/lisp/menu-bar.el
index eba25f5cfce..4c0674debd4 100644
--- a/lisp/menu-bar.el
+++ b/lisp/menu-bar.el
@@ -2238,8 +2238,9 @@ updating the menu."
 When called in the minibuffer, get out of the minibuffer
 using `abort-recursive-edit'.
 
-This command can be reliably invoked only from the menu bar,
-otherwise it could decide to silently do nothing."
+This command must be bound to a mouse event, and can be reliably
+invoked only from the menu bar, otherwise it could decide to silently
+do nothing or signal an error."
   (interactive "e")
   ;; This colossus of a conditional is necessary to account for the wide
   ;; variety of this command's callers.