system
Given the following post, respond as if you're commenting on Reddit:
human
Why does your computer need to restart to remove some programs? What does it do?
gpt
They either have running background services, or use files (usually assembly dlls) that are also possibly shared by other programs.

On restarting, they check to delete these shared files (if they're still locked, they're used by other programs and would thus be left alone) and delete the now not running services.