Doctor Who has change and evolution ingrained in its DNA, a trait that is both one of its biggest selling points, as well as its most forefront point of contention among fans.
Whenever the show gets a major refresh in the form of a brand-new Doctor, it's exciting to see how the latest actor to play the Time Lord will fare in the role, but at the same time, it's sad to see a great Doctor pass the torch and leave the TARDIS behind.
Despite the heartbreak that a Doctor's regeneration can bring, one of the reasons the show has been able to survive over 50 years - when so many others have come and gone in a fraction of that time - is because it's able to grow, adapt and change.
Doctor Who simply wouldn't be Doctor Who without a different actor portraying the main character every couple of years, but that doesn't mean we have to like each incarnation. Every Doctor Who fan has their favourites and least-favourites, and of the 13 main faces we've seen so far, some definitely stand out above the rest.