You're not the only one. All of them are CDs.

What happens is that when using a GCD and quickly tapping a CD skill, the animation will play slightly then get cancelled. That's because of the nature of the game's lag, how it ques moves based on animation lockdowns and the fact that theres constant packet loss when sending data.

Surprisingly you haven't mentioned the most obvious one which are Ninjas with their mudras. Those who suffer of the above pay it with less dps and mudra fuckups, which is the worst of the worst.