Adamantine vs. Natural Armor

[Rakeesh]

Playgrounders,

I was wondering that since natural armor bonuses do things like toughen a creature's hide, thicken its skin, etc. etc., why does it apply to adamantine or starmetal or other hardness-bypassing materials? Am I understanding the rules properly, and it's just a little bit of an inconsistency, or what exactly?

[Diggorian]

Hurting things is a combination of how hard you hit (damage) and how well you hit (attack roll). Natural armor is difficult to hit well, the skin isnt so much thicker as its striated in a way to make it hard to hit meat.

Alligators have natural armor. Hurting one with a melee weapon isnt hard because they're like stone (hardness, DR), it's because their scale is hard to puncture (higher AC).

[Matthew]

As the RAW stands Armour provides an Armour Bonus, but it generally not any Damage Reduction. The same applies to natural Armour. The idea is that Armour deflects Damage, rather than absorbing it. This is, of course, not an entirely satisfactory abstraction, which is why the Damage Reduction Variant Rules exist.