diff --git a/modules/core/src/main/resources/default.scala-steward.conf b/modules/core/src/main/resources/default.scala-steward.conf
index 45348f662e..17cfb7cf6d 100644
--- a/modules/core/src/main/resources/default.scala-steward.conf
+++ b/modules/core/src/main/resources/default.scala-steward.conf
@@ -4,6 +4,9 @@
 //   Changes to this file are therefore immediately visible to all
 //   Scala Steward instances.
 
+// Repos whose last commit is older than this threshold are considered
+// inactive and are ignored. This setting can be overridden with a greater
+// value in your own repo config file.
 inactivityThreshold = "270 days"
 
 postUpdateHooks = [