The Mysterious Disappearance of the Jayce Shockblast

I've been playing a whole bunch of Jayce, lately, and I've realized that sometimes when shooting the Q (not through the Acceleration gate), the orb disappears into the ground. It doesn't blow up or anything. It's just gone. This happens a lot, actually, where it'll just disappear and not give vision at all. Is this a bug ...or..?