7. BBC Can Reuse Past Clips Cheaply
'The Eleven Doctors' was so badly wanted by so many fans - and quite a few Doctors themselves - that no matter how the Classic series was represented in 'The Day of the Doctor', it would've been a disappointment to many. Obviously, we don't have eleven living Doctors anymore. Yes, we could've brought some back with CGI but expense plays a role in that. Bizarrely though, the cheap alternative isn't actually that cheap. The BBC have to pay to use clips from their own back-catalogue. Seriously. They don't own the rights to past footage, and so they have to pay for those rights. So whilst you might've preferred to see William Hartnell reanimated for your viewing pleasure, what you did see probably cost just as much.