To my astonishment, Windows 10 does not really do a full restart or shutdown when you select the according menu entries from the start menu.

This is bad, because if you want to do a restart, you want to do this because something is wrong with the system. So then a partial restart is exactly not what you usually want.

You still can do a real restart via commandline:

%windir%\System32\shutdown.exe /r /t 0

When you rightclick on the desktop and select New/Shortcut and put in the commandline above you create an icon on the desktop with which to do a real restart.
Also, it may be good for the system to do a real shutdown once a week. Here’s the commandline.

%windir%\System32\shutdown.exe /s /t 0