diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 879949012ef37e2a9045dd75d761f3d70c929050..1f5144393630bd51b97caf13185600fe206b0006 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -14,7 +14,9 @@
 # As above, but rules for running when the scheduler triggers the pipeline.
 .schedule_rules: &RUN_ON_SCHEDULE
   rules:
-    # There are multiple schedules so make sure this one is for us.
+    # There are multiple schedules so make sure this one is for us.  The
+    # `SCHEDULE_TARGET` variable is explicitly, manually set by us in the
+    # schedule configuration.
     - if: '$SCHEDULE_TARGET != $CI_JOB_NAME'
       when: "never"