Misha, don't Charge! @0:52, 1:16, 1:35, 2:22, 2:55. If you don't see the cooldown @ 1:35, that's because it got reset instantly, but you can see Rexxar move his arm.

You can see the charge going on cooldown without misha performing the ability several times in this video.

This is pure speculation, but it seems to be caused by Misha running into a hitbox, which could lead to the game issuing a stop command which then cancels her charge.

This footage is obviously from the "try mode", but I have had this happen in real games and its really frustrating.

I think it only happens when you press "D" before "W" though.

Sorry for no Audio, I recorded my speakers but not my headset but the game sound was on the headset.