"Like it or not modern operating systems all require
updates and patching. Some updates require updates to underlying
libraries and utilities. Intelligent systems will download and
update those at the same time. By using software that can be freely
distributed, then you can take advantage of this kind of
intelligent feature. Most GNU/Linux distributions handle this
through their package-management tools. The really intelligent ones
will warn if you updating a library is going to break other
software, and because of the sharing nature of free software that
means most GNU/Linux distributions. The mistrusting nature of
proprietary software vendors means one package update could break
some other software on your system.
"Conversely because of the mistrusting nature of proprietary
software vendors ("It's our code you can't have access to it!"),
you can get into situations where one package update requires a
library update which will break some other software on your system.
Anybody who has had to repair a Windows system that was broken by
upgrading the anti-virus suite will know what I mean here."