Windows Update Message Visibility
Windows Update messages are currently buried and barely visible on Windows 8+.
For example, if you set Intune to only update Windows after prompting the user to do so, there isn't actually a prompt on Windows 8+. The user is only notified of updates with a yellow mark on the system tray Intune Agent icon.
A pop-up box should always be on top of other windows and should get primary focus when it is triggered based on the policy settings.