Turrets are literally useless
No, really:
https://plays.tv/video/5a040c9687c5a3bfcd/turret-does-no-damage
Gnar tanks 4 turret shots at 700 hp with no defense, and the 4th shot actually does 40 damage (?!). Lucian then tanks 2 more shots from a fully stacked tower for shits and giggles because it doesn't even deal a third of his max HP.