diff --git a/content/en/docs/concepts/storage/volumes.md b/content/en/docs/concepts/storage/volumes.md
index e87d339ac5..50f7bf62a2 100644
--- a/content/en/docs/concepts/storage/volumes.md
+++ b/content/en/docs/concepts/storage/volumes.md
@@ -1133,6 +1133,7 @@ spec:
     volumeMounts:
     - name: workdir1
       mountPath: /logs
+      # The variable expansion uses round brackets (not curly brackets).
       subPathExpr: $(POD_NAME)
   restartPolicy: Never
   volumes: