[{quoted}](name=Irelia Bot,realm=NA,application-id=3ErqAdtq,discussion-id=72FoxrOy,comment-id=,timestamp=2016-12-11T17:36:58.399+0000)
And what if there was 2 variations, one being thornmail and the other building from warden's mail to reduce attack speed.
By the logic of LW items being balanced, items like this would be also be able to be balanced and "healthy" for the game.
Effectively bypassing a large part of a champs bought stats.
All of the arguments in favor of Last Whisper items would also apply to an item like this. Including things like it not being hidden power.
TL;DR~~~ Tanks are designed to be outscaled and these items exist so that tanks aren't the only ones alive at the end of fights, which would result in average game times of likely 50 min+
I have a feeling you're just posting on here for the sake of sounding dumb and actually do have a brain, but I'll explain anyways.
Those armor pen items scale damage in a percentage form, especially
.
They are meant to be bought mid-game or late-game to get their best damage increase, they exist to outscale tanks (which is one of their intended weaknesses).
If tanks had an equal type of item, they would never be outscaled. That means all fights would end with tanks surviving, which in turn means that no turrets will be taken, no objectives like baron would ever come out of a fight etc.
These items exist so that it gets to a point where you can no longer beat carry champions with pure stats, you have to outplay them at a point.
It's also fair to point out there is not a single tank item above 3000 gold in cost (this is counting pure tank items, not fighter items like black cleaver)
They spike off of their items quicker than other champions, this is their strength over getting outscaled later.