No, Windows will NOT restart now

‘StupidSoft PointlessTool X has been installed. Your computer will now be rebooted. Press OK to reboot’.

What gives a piece of software the right to decide when I reboot my computer? Its such a nonsensical myth anyway. It just doesn’t have to be necessary to shut down the whole operating system simply to install an application. How can Windows be taken seriously as a server platform while this sort of thing is still going on?