Originally Posted by HaIfhearted
You seem to have forgotten that Cleaver also gives 50 AD and LW gives 40.
I honestly don't see how "raw AD numbers take a hit" when you stack penetration.
Agreed, but that is still less than IE and SB provide. Not by much, but the point stands.
Also, they give up attack speed and critical strike chance which is all part of the multiplicative damage scaling appreciated by AD Carries. Yes, Youmuu's gives all those things - but in small quantities compared to an AD Carry build.
Some champions have the AS (Fiora, Tristana, Xin) or Crit Chance (Tryndamere) covered completely or in part by their kits, but every champion has to give up something, and they all have to give up survivability.
The real kicker is that a champion like Garen or Wukong can build Black Cleaver + tank items while his squishy AD Carry buddy builds heavy AD + Last Whisper. The AD Carry benefits from the Black Cleaver debuff hitting the entire enemy team, on top of whatever other penetration/reduction they may have (Corki). The bruiser remains a great damage soak. I don't know if that was intended, but perhaps a great fix for Black Cleaver would be to change the passive to % penetration?