diff --git a/documentation/ref-manual/ref-variables.xml b/documentation/ref-manual/ref-variables.xml
index 0f86def5ca..acb1446386 100644
--- a/documentation/ref-manual/ref-variables.xml
+++ b/documentation/ref-manual/ref-variables.xml
@@ -951,6 +951,8 @@ Core layer for images cannot be removed
                     Typically, you configure this variable in your
                     <filename>local.conf</filename> file, which is found in the
                     <ulink url='&YOCTO_DOCS_DEV_URL;#build-directory'>Build Directory</ulink>.
+                    Although you can use this variable from within a recipe,
+                    best practices dictate that you do not.
                     <note>
                         Use the
                         <link linkend='var-IMAGE_FEATURES'><filename>IMAGE_FEATURES</filename></link>