Any decent program will alert the user that downloads are ready to install (or otherwise follow default OR user defined protocol concerning that)
I firmly believe that my computer is in cahoots with all OTHER computers, and they have nothing better to do than to arrange downloads and installation of system critical files precisely when I'm compliling a Java, C++ (or VB) project for school (or doing something else that just plain shouldn't be prone to memory leak issues). Nor to minimize the potential complications if MS WU are being downloaded and installed concurrently.
There are apps on my system that alert me to "issues" that have been observed (requiring my permission to allow prior to reboot), and there's this other thing either installing or downloading.
EEK.
Just doesn't feel good.