[SATLUG] OT: FreeBSD - make buildworld

[Sean Carolan]

> make buildworld is to rebuild the core OS userland.
> make buildkernel KERNCONF=<your conf file> is to rebuild the FreeBSD kernel.

Ok, I get this but *why* would you rebuild your entire OS userland
from source?  Is it because of security flaws, new features,
stability, etc?  Could you just install the latest STABLE version and
not update it at all?  Or only update critical security
vulnerabilities?