Skill has no effect but still goes on cooldown.

[Sinisterror]

https://imgur.com/a/3sGQPad

You can see me pressing A1 and Frenzies disappearing and Animation of the attack, but no dmg yet cooldown. Why does this happen in RoR? This happens for ranged chars all the time. For Melee its a bit more rare but it does happen, never happened live. Can someone explain why and how? Yes target dying obviously but if target is dead same moment i use ability it shouldnt fire.

I have tried to, and succeeded in spamming 2-3 abilities at same time on target dummies and getting cooldown on 2 abilities at the same time but obviously only 1 of the abilities happen, and its not Ui bug. It shouldnt be this easy to break