[driverdan]

Correct. No one should be able to push out arbitrary code without explicit user approval.

[SquareWheel]

Users have a terrible habit of not running updates. Years of botnets suggest that automatic updates are probably the way to go.

[Sohcahtoa82]

In a perfect world, where all users are smart, sure.

But we're living in a world where there are still people running unpatched Windows XP boxes still vulnerable to MS08-067.

If it weren't for Windows automatically installing updates, I imagine at least half of home users would still be vulnerable to Eternal Blue.