Where I live we have very frequent power outages. The way libreelec is configured, when our power goes out and then comes back on the Pi turns on. As a work-around I have set a shutdown timer, but for keeping the device off that's not ideal since I have to strike a compromise with keeping the device on without anything playing even for extended times.
So, my wish would be to set it up such that when power returns by default the Pi stays off and only with a button press will it boot.