I think this may be a regular thing.
Microsoft UI design quirk #1 – Windows Updates
If a restart is required to complete updates, then why:
– is there no “install updates and restart” option on the Shut Down page (only available for Shut Down) – a consistency thing
– is there no “shut down” option instead of “restart now” after performing updates manually
– do automatic updates only allow you to restart the computer after a countdown timer
Talk about a case of “can’t make up their mind”…