The Flash, Season 3

Joe:
Listen,... you were right. I do treat Barry differently than I treat you. But not because I think Barry's better than you.

Wally:
Then why?

Joe:
Wally, you're a lot like I was when I was a kid. You're fearless, and you take risks, and that makes you a handful just like I was. And now you're getting powers. That, alone, would make me nervous because I know what I would have done if I got powers. But you're not getting your speed the same way Barry got his. You're getting your speed the same way Magenta and the Rival got theirs. So it's not that I don't trust you, Wally, it's just that I don't trust what's going on with you right now, and that scares the living hell outta me.