Castrovalva - S19-E1
Question: Why does The Master come up with these ridiculously elaborate plans to kill The Doctor when he could have killed him at the beginning of the first episode, just after his regeneration, when he was very weak?
Tiger Left, Tiger Right - S2-E6
Question: The episode first aired October 1964. How could a Ford Mustang be seen in the episode if that car wasn't available until April 1965?
Answer: Production vehicle models aren't in sync with the calendar year. The '65 Mustang began production in March 1964 and first sold in April 1964, before it was "introduced" the following year. I don't know which model was seen in the episode, but the 2+2 fastback was sold in September 1964. The 1964 film "Goldfinger" uses a 1965 Mustang as part of Ford's product placement. Basically, in the 1930's, FDR ordered automakers to release vehicles in the fall of the preceding calendar year "as a means of facilitating regularization of employment in the industry." Now, automakers can release new models as early as Jan 2 of the preceding year.
Chosen answer: Because he wouldn't be satisfied simply killing The Doctor when he's weak and infirm. The Master needs to outsmart him.
Captain Defenestrator