diff --git a/core/modules/system/system.api.php b/core/modules/system/system.api.php
index 5360a83..8807899 100644
--- a/core/modules/system/system.api.php
+++ b/core/modules/system/system.api.php
@@ -2695,12 +2695,14 @@ function hook_update_N(&$sandbox) {

   $sandbox['#finished'] = empty($sandbox['max']) ? 1 : ($sandbox['progress'] / $sandbox['max']);

+  if ($sandbox['#finished'] > 1) {
+    // In case of an error, simply throw an exception with an error message.
+    throw new UpdateException('Something went wrong; here is what you should do.');
+  }
+
   // To display a message to the user when the update is completed, return it.
   // If you do not want to display a completion message, simply return nothing.
   return t('The update did what it was supposed to do.');
-
-  // In case of an error, simply throw an exception with an error message.
-  throw new UpdateException('Something went wrong; here is what you should do.');
 }

 /**