I'm using Crunchbang Linux on my laptop.
I noticed a strange behavior of the package manager: when installing a package from the official repo (`libdirectfb-extra` in my case) `apt` told me that a bunch of packages were no more needed (including `xflux`, `obconf`, `obmenu` and other applications that I use frequently). I proceeded to the installation of the package, but then `apt` removed all the packages that it said to be not needed.

What does it mean? Why does it happen? I don't update the system very frequently, is that the cause?