diff --git a/core/modules/system/tests/modules/new_dependency_test/new_dependency_test.install b/core/modules/system/tests/modules/new_dependency_test/new_dependency_test.install
index c099059fd4..e500d72b22 100644
--- a/core/modules/system/tests/modules/new_dependency_test/new_dependency_test.install
+++ b/core/modules/system/tests/modules/new_dependency_test/new_dependency_test.install
@@ -9,6 +9,7 @@
  * Enable the new_dependency_test_with_service module.
  */
 function new_dependency_test_update_8001() {
-  debug('Running the new_dependency_test_update_8001.');
+  // During the update hooks the container is cleaned up to contain only
+  // services that have their dependencies met. Core services are available.
   \Drupal::getContainer()->get('module_installer')->install(['new_dependency_test_with_service']);
 }