At the end of Tuesday's episode of The Flash, where King Shark is trying to kill Barry, Zoom's identity was revealed! But that's not what I want to talk about in this article. You can look up what that might mean somewhere else.
What I want to focus on is the fact that Zoom killed Jay Garrick. He was holding Jay's stagnant body and threw it away, saying how it was problematic. But why would this be? Didn't he mean to kill Jay Garrick? Answer: NO.
Who did Zoom want to kill?
Remember how Zoom held Wells to keep him from getting through the breach? Barry got him free and ran the two through. Zoom must have gone through after them, aiming to keep Wells from getting to Earth-1 and surviving. He didn't expect Jay to be standing in front of the breach. So Zoom killed him, not intending to grab him but Wells instead.
Which means that Zoom killed a speedster that he could have taken the speed from once it was restored. That could be why it's problematic, or there could be another reason tied to Zoom's real identity which, honestly, is still at question. Even though we've seen his face, we don't know his whole story. Good thing the writers only have 8 episodes to reveal and resolve it all.