Different Shutdown process from Kodi or ssh

[Gauner]

Ok, thank you very much for clarification.
I already opened a issue on github.
I added there my finding about the different ways that the system changes the runlevel when shutdown from Kodi.

Is there a similar folder like /lib/systemd/system-shutdown that executes scripts at startup? Or is my consideration correct, that startup scripts must go into the rc?.d or rc.local, while shutdown scripts go into /lib/systemd/system-shutdown? So, there's no consistent way of executing a script on startup and shutdown?