Because, Barry. [Gwen is going to kill him for this. Cisco may well join her. But Harrison is leaving, he's leaving Barry behind, he's leaving Eobard behind and he has no idea how that's going to affect the distance that Eobard is keeping from Barry, and—

And he wants Gwen and Cisco to be happy. Frankly. He does. He's seen them together, all three of them and then just the two of them, and he's seen both of them trying to recover from finding this new Barry who doesn't know them...they deserve to be happy.]

They are—were, and are—in love with you. And you were with them, before you left. It worked, and you were happy. I know you don't remember it, why would you, this you has never been here before, but. [He spreads his arms, lets them drop again. There it is. Can't be unheard.]