He sees The Winter Soldier get pushed down a final time, the technicians wary but firm.
He forces himself to look, although he hates this part.
He doesn't care about the Winter Soldier. If Hydra told him to, he'd put a bullet in his brain without thinking, without questioning. He's just a machine, a tool that Hydra uses to further their goals.
But as the machine begins to clamp down over the man's limbs and cover his face, Rumlow swallows hard.
He sees his future.
One day, when Hydra decides it's necessary, he will be strapped down, his mind drained. His own body will spasm in pain as a machine rips into what is left of his memory.
He tries to stand firm as it happens, tries to hide his nervousness as the Winter Soldier is torn apart inside.
When it ends, The Winter Soldier sags in the chair, shaking and trembling.
Pierce turns to him, smiling. "Well, that went well, don't you think?"
Rumlow gives the only answer that's allowed.
"Yes, sir."