Wasn't this what he wanted? The Flash at his mercy, succumbing to his power, proving once and for all that he was the stronger of the two of them and that even if he hadn't been able to become everything that the Flash was like he'd once hoped, he'd proved himself more capable by becoming everything that he wasn't. Wasn't this exactly what he had hoped for for the longest time?
Except it wasn't. Not really. This was a hollow victory. What he'd wanted, in this endeavor, had changed to adapt to the circumstances that he'd found himself in. And right now, Barry willingly sacrificing himself without even attempting to preserve his life, doing it without the ultimatum of having to preserve the life of someone else...
This wasn't what he'd wanted.
"No," Thawne said, surprising himself more than he was probably surprising Barry. "Not like this. Not with you acting as though I'm doing you a favor."