diff --git a/core/lib/Drupal/Core/Entity/EntityChangedInterface.php b/core/lib/Drupal/Core/Entity/EntityChangedInterface.php
index 5e87c62..9a6c194 100644
--- a/core/lib/Drupal/Core/Entity/EntityChangedInterface.php
+++ b/core/lib/Drupal/Core/Entity/EntityChangedInterface.php
@@ -9,6 +9,9 @@
 
 /**
  * Defines a common interface for entity change timestamp tracking.
+ *
+ * This data may be useful for more precise cache invalidation (especially
+ * on the client side) and concurrent editing locking.
  */
 interface EntityChangedInterface {