[Distutils] The Update Framework, integrate into PyPI?

I read the RoadMap (Thank you Marcus Smith) and came across this:

An effort to integrate PyPI with the “The Update Framework” (TUF). This is specified in PEP458

I see a trend to immutable systems everywhere. Updates are a pain. Building new systems is easier. With current hardware and good software it is easier to build new systems instead of updating existing systems. It is like from pets to cattle: - pets: you give them names and care for them (do updates) - cattle: you give them numbers and if they get ill you get rid of them. Maybe I am missing something. But why is there an effort to create "The Update Framework”, and why integrate it with pypi? Regards, Thomas Güttler -- http://www.thomas-guettler.de/