diff --git a/man/systemd.exec.xml b/man/systemd.exec.xml
index d2553b287c4..7bdac1c1d53 100644
--- a/man/systemd.exec.xml
+++ b/man/systemd.exec.xml
@@ -1184,7 +1184,11 @@
         details. Defaults to <option>shared</option>. Use <option>shared</option> to ensure that mounts and unmounts
         are propagated from systemd's namespace to the service's namespace and vice versa. Use <option>slave</option>
         to run processes so that none of their mounts and unmounts will propagate to the host. Use <option>private</option>
-        to also ensure that no mounts and unmounts from the host will propagate into the unit processes' namespace. Note that
+        to also ensure that no mounts and unmounts from the host will propagate into the unit processes' namespace.
+        If this is set to <option>slave</option> or <option>private</option>, any mounts created by spawned processes
+        will be unmounted after the completion of the current command line of <varname>ExecStartPre=</varname>,
+        <varname>ExecStartPost=</varname>, <varname>ExecStart=</varname>,
+        and <varname>ExecStopPost=</varname>. Note that
         <option>slave</option> means that file systems mounted on the host might stay mounted continuously in the
         unit's namespace, and thus keep the device busy. Note that the file system namespace related options
         (<varname>PrivateTmp=</varname>, <varname>PrivateDevices=</varname>, <varname>ProtectSystem=</varname>,