[tex-live] "After installation, get package updates from CTAN"

[mike _]

When running the 2013 installer from DVD there is an option "After
installation, get package updates from CTAN" which is 'yes' by
default. Given the wording of the option and what the documentation
says, my understanding is that when this option is set to 'yes' all
outstanding updates are automatically retrieved from a CTAN mirror and
installed as part of the install process. However I don't see anything
in the installer output that indicates that anything is being
retrieved from a CTAN mirror and if I run "tlmgr update --all" after
the installation is finished there's about 140 updates get retrieved
and installed. This is the case on Linux and Windows 7.

Am I misunderstanding what that option means, or is it broken, or
something else?

thanks,

mike