The news that Whittaker and showrunner Chris Chibnall are leaving the Doctor Who franchise after three seasons "comes as a relief — not because of Whittaker's departure, but because of Chibnall's, who as showrunner is ultimately responsible for what has been the most disappointing era of the show's modern incarnation," says Liz Shannon Miller. "And the reason why it's been such a letdown isn't hard to figure out: The show never really believed that a female Doctor who could serve as the lead." As Miller points out, previous Doctors had a single female companion. "Meanwhile, when Whittaker was first introduced as the 13th Doctor, she did so after crashing into the lives of Essex residents Graham (Bradley Walsh), Ryan (Tosin Cole), and Yasmin Khan (Mandip Gill), who then became her loyal 'fam,' game for ongoing travels," says Miller. While the trio made Doctor Who more diverse, they also took away from Whittaker as the Doctor. "They sucked up the oxygen, is the best way of putting it," says Miller. "The problem is that the typical Doctor Who episode is a stand-alone adventure in a new time period and location, featuring a brand-new supporting cast. This means these episodes require a whole lot of set-up early on, and there's frankly not a lot of screen time to spare on additional character stories. Dropping into that mix the Doctor and a companion (maybe two, if a boyfriend or Captain Jack was along for the ride) worked out fine as a rule. But three companions, all of whom were heavily featured in the plots for these episodes, meant that more often than not, the Doctor had to take a backseat on her own show. Even when the Doctor did get a bit of a storyline focusing on her past, it came largely in the form of longtime nemesis The Master (Sacha Dhawan in this incarnation) shouting at her while she lingered in prison." Miller also notes that Whittaker's seasons have been shorter than her Doctor Who predecessors. Seasons 1 through 10 consisted of 12 to 13 episodes. Whittaker's first two seasons had 10 episodes each and her final season will have only six episodes. Additionally, Whittaker's stint hasn't had the "companion-lite" episodes that have showcased previous Doctors. ALSO: Michaela Coel, Richard Ayoade and Olly Alexander are some of the fan picks for the next Doctor.