Because if you're going to build something like that, you could just build Banner of Command and that still has use after all the turrets are gone. Still wouldn't build either of them though unless I was trolling something. --- Rule #1 of Resident Evil: Don't catch the sunglasses. GT - Judgement Blade
Because Warmog's laughs at turrets anyway. I honestly have never seen the item built since its been released.
Seen it once on a support Taric. It made them bold and they dove onto an Ahri, Vayne, Ali, & Xin thinking they could kill'em all. Yeah both times he used it they gave us 3 or 4 kills and took nothing, think he never used it/sold it after those 2 failed attempts.
I do like the particle effect it has on the turret though, thats cool. But the item is garbage as a whole sans particle effect.