- <para>If a command is run with timer options such as <option>--on-calendar=</option> (see below), a transient timer
- unit is created alongside the service unit for the specified command. Only the transient timer unit is started
- immediately, the transient service unit will be started when the timer elapses. If the <option>--unit=</option>
- option is specified, the <replaceable>COMMAND</replaceable> may be omitted. In this case,
- <command>systemd-run</command> creates only a <filename>.timer</filename> unit that invokes the specified unit when
- elapsing.</para>
+ <para>If a command is run with path, socket, or timer options such as <option>--on-calendar=</option> (see below),
+ a transient path, socket, or timer unit is created alongside the service unit for the specified command. Only the
+ transient path, socket, or timer unit is started immediately, the transient service unit will be triggered by the
+ path, socket, or timer unit. If the <option>--unit=</option> option is specified, the
+ <replaceable>COMMAND</replaceable> may be omitted. In this case, <command>systemd-run</command> creates only a
+ <filename>.path</filename>, <filename>.socket</filename>, or <filename>.timer</filename> unit that triggers the
+ specified unit.</para>
+
+ <para>By default, services created with <command>systemd-run</command> default to the <option>simple</option> type,
+ see the description of <varname>Type=</varname> in
+ <citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry> for
+ details. Note that when this type is used the service manager (and thus the <command>systemd-run</command> command)
+ considers service start-up successful as soon as the <function>fork()</function> for the main service process
+ succeeded, i.e. before the <function>execve()</function> is invoked, and thus even if the specified command cannot
+ be started. Consider using the <option>exec</option> service type (i.e. <option>--property=Type=exec</option>) to
+ ensure that <command>systemd-run</command> returns successfully only if the specified command line has been
+ successfully started.</para>