Capaldi won't last that long sadly. The show make actors more popular than the BBC can afford. Most actors want to work. They don't want to spend nine months promoting a 13 episodes TV show that took three months to produce. The crappy pay, limited actual yearly output of episodes, but expanded marketing commitment, all of this is at the root of the quick turnover both in Doctors and Companion.
from overview for madhi19 http://ift.tt/1EW4FYk