diff --git a/_im-plugin/ism/policies.md b/_im-plugin/ism/policies.md
index 16c641d1..e6760197 100644
--- a/_im-plugin/ism/policies.md
+++ b/_im-plugin/ism/policies.md
@@ -126,7 +126,7 @@ Parameter | Description | Type | Required
 
 ### read_only
 
-Sets a managed index to be read only. When an index is read only it doesn't refresh.
+Sets a managed index to be read only. Read-only indexes don't refresh.
 
 ```json
 {