Rise of the Cybermen (1) - S2-E8
[Mickey has his finger on a button on the console.]
The Doctor: Um... What're you doing that for?
Mickey: 'Cause you told me to.
The Doctor: When was that?
Mickey: About half an hour ago.
The Doctor: Um. You can let go now.
Mickey: Well, how long's it been since I could've stopped?
The Doctor: Ten minutes? Twenty? ... Twenty-nine?
Mickey: You just forgot me!
The Doctor: No, no, no! I was just...I was just...I was calibrating. I was just...no, I know exactly what I'm doing.
Chosen answer: The Master knows that deep down, he deserves death for the crimes that he's committed throughout his life, and since he regards The Doctor as his arch-foe, he expects it to be at his hands. The fact that The Doctor is still willing to forgive him for all of his crimes hurts him more deeply than death would.
Captain Defenestrator