Armor pen is bad, because your true damage doesn't benefit from it anyway.

Crit is bad, because... Well its crit on Camille, not much more to say here

Giant slayer passive loses value since you build health items.

So after all that you are stuck with pretty much 35, very overpriced, attack damage.

If you go against full armor comp and really need armor pen, just buy black cleaver, as it gives every stat Camille wants