Other than getting less items, the most tilting thing in TFT...

is the consistency of abilities

You kill an Aatrox during his ability, it still goes off and murders your frontline. Your aatrox dies mid ult and it does no damage. Your poppy targets 1 person with their ult, the enemy poppy is consistently hitting 2 and 3 man ults. Champs dying with full mana bars, (not silenced) and just sitting there, not ulting or autoing.

absolutely tilting