aptitude and package removal

[Willy K. Hamra]

so today, i ran aptitude full-upgrade, i saw on top that it was going to
remove grub-doc.
i wanted to see why the package is going to be removed, so i typed
beside the (y/n/?) question "i grub-doc", and the answer was:

Do you want to continue? [Y/n/?] i grub-doc

Package: grub-doc

New: yes

State: installed; will be removed because nothing depends on it

Automatically installed: no

Version: 0.97-29ubuntu58

Priority: optional

Section: doc

as you can see, it was manually installed, i like to have the doc
packages for quick references since internet is not always available or
too slow to look up for help. it's going to be removed because nothing
depends on it. but... there are tons of other packages that nothing
depends on them :S
according to my understanding, a package is usually removed when nothing
depends on it, and was automatically installed as a dependency of
another package. if the other package is removed, it gets removed as well.
but this... it was *manually* installed. why is it flagged for removal?

-- 
Willy K. Hamra
Manager of Hamra Information Systems
Co. Manager of Zeina Computer & Billy Net
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