diff --git a/lib/utils/threading.py b/lib/utils/threading.py
index 7bb90d1b4..f0c228876 100644
--- a/lib/utils/threading.py
+++ b/lib/utils/threading.py
@@ -12,6 +12,7 @@ class ExitThread(InkstitchException):
     pass
 
 
+# A default flag used for the main thread.  It will never be set.
 _default_stop_flag = threading.Event()