I'm not sure if this is a bug (I'm a noob to ESO, so it may be a setting I accidentally flipped somewhere) but I've been having issues with Endless Hail lately. When I first started using it, activating it the first time gave me a targeting ring, and I could move that around to position it. Hitting the key a second time fires it off in the targeted area.
Now, when I hit the key, it fires off immediately at the point I'm looking at. I'm on PC, if that makes a difference.