[tbrock]

Yeah but, if unpatched, it would have downloaded more as part of a botnet.

[detaro]

Windows 10 is not a "a patch"

[Karunamon]

Windows Update downloads more than "patches". It has been used in the past to distribute standalone tools and service packs.

[function_seven]

It has never wholesale upgraded the OS to a new major version. Nobody expects it to.

[9872]

And that's a large part of why Windows security has always been terrible. While we may not have expected it, that just means we were pleasantly surprised.

[cousin_it]

A security update shouldn't take 6 GB of space.

[9872]

How much space should it take?

[ubercow13]

Windows 8.1 is supported until 2018