I've mentioned this before (and if I haven't, why haven't you been reading my mind, hmm?), but it's always seemed to me that the BBC is more or less in general is oriented toward what in the US would think of as mini-series. An end is (almost) always in sight there, even when it's abrupt, whereas the production teams, the sponsors and the viewing audiences are all happy to think that a show will go on forever over here until it's booted off the air via cancellation blurb on the newswires/Internet. It's why we've had so many shows go on past their sell-buy date, as well as shows that just end (though, admittedly, that was more or a feature of shows in my youth, when the world was no so Internet-interconnected).

Why, I ask.