Jarvan IV Ultimate

Ok so I have been playing for some time. He's been one of my mains since he came out. When Jarvan dies mid ultimate, his ultimate is cancelled, but will go on cool down. This happens to me a lot, so I've never question it. I just assumed if it went off even if I died, it would be overpowered or something. So here's my question: Has this always been normal, or is it a bug that's never been resolved? It does make quite a big difference, especially since it puts it in cool down, let alone not even going off.