diff --git a/man/NetworkManager.conf.xml b/man/NetworkManager.conf.xml
index 8135455d50..9ddd2b55a0 100644
--- a/man/NetworkManager.conf.xml
+++ b/man/NetworkManager.conf.xml
@@ -502,19 +502,29 @@ no-auto-default=*
         </varlistentry>
         <varlistentry>
           <term><varname>unmanaged-devices</varname></term>
-          <listitem><para>Set devices that should be ignored by
-           NetworkManager.
-          </para>
-          <para>See <xref linkend="device-spec"/> for the syntax on how to
-           specify a device.
-          </para>
-          <para>
-            Example:
-            <programlisting>
+          <listitem>
+            <para>Set devices that should be ignored by NetworkManager.
+            </para>
+            <para>
+              A device unmanaged due to this option is strictly
+              unmanaged and cannot be overruled by using the API like
+              <command>nmcli device set $IFNAME managed yes</command>.
+              Also, a device that is unmanaged for other reasons, like
+              an udev rule, cannot be made managed with this option (e.g. by
+              using an <literal>except:</literal> specifier).
+              These two points make it different from the <literal>device*.managed</literal>
+              option which for that reason may be a better choice.
+            </para>
+            <para>See <xref linkend="device-spec"/> for the syntax on how to
+              specify a device.
+            </para>
+            <para>
+              Example:
+              <programlisting>
 unmanaged-devices=interface-name:em4
 unmanaged-devices=mac:00:22:68:1c:59:b1;mac:00:1E:65:30:D1:C4;interface-name:eth2
 </programlisting>
-          </para>
+            </para>
           </listitem>
         </varlistentry>
       </variablelist>