Объясните поведение systemd

/bin/sh -c 'scriptname 2>/dev/null'

[Unit]
Description=for intelfx example
After=network.target

[Service]
Type=simple
ExecStart=/usr/bin/cmt
User=pi

[Install]
WantedBy=multi-user.target

#!/usr/bin/env bash

action='/home/pi/script.sh 2>/dev/null &'


while true; do
    if [[ условия старта ]]; then
        DISPLAY=:0 $action
    else
        echo "Kicked"
    fi
done

$ cat test2.sh
#!/bin/bash

echo "test2: $0 $*"

$ cat test.sh
#!/bin/bash

action="/home/operator/test2.sh 2>/dev/null"

DISPLAY=:0 $action

$ ./test.sh
test2: /home/operator/test2.sh 2>/dev/null

/home/pi/script.sh 2>/dev/null &