diff --git a/docs/tasks/configure-pod-container/configure-pod-configmap.md b/docs/tasks/configure-pod-container/configure-pod-configmap.md
index ab102aecb8c06..35f81e6dfb47e 100644
--- a/docs/tasks/configure-pod-container/configure-pod-configmap.md
+++ b/docs/tasks/configure-pod-container/configure-pod-configmap.md
@@ -273,6 +273,10 @@ very
 You can project keys to specific paths and specific permissions on a per-file
 basis. The [Secrets](/docs/concepts/configuration/secret#using-secrets-as-files-from-a-pod) user guide explains the syntax.
 
+### Mounted ConfigMaps are updated automatically
+
+When a ConfigMap already being consumed in a volume is updated, projected keys are eventually updated as well. Kubelet is checking whether the mounted ConfigMap is fresh on every periodic sync. However, it is using its local ttl-based cache for getting the current value of the ConfigMap. As a result, the total delay from the moment when the ConfigMap is updated to the moment when new keys are projected to the pod can be as long as kubelet sync period + ttl of ConfigMaps cache in kubelet.
+
 {% endcapture %}
 
 {% capture discussion %}