Not only are the Daleks the Doctor's most iconic and oldest recurring villains, they're also the most overused. To date, the Daleks are estimated to have featured in 26 storylines in the show's history, putting in an appearance in every single series of the show since its return in 2005 and been the central villains in thee out of seven finale episodes (five if you count Time of the Doctor and The Day of the Doctor). What makes this even worse is the number of times the Daleks have been "permanently" destroyed by the Doctor and his companions. Almost every time an army of Daleks has appeared, they have been destroyed "forever", only to resurface the next time the Doctor needed a major threat to face. Enough is enough. Because they appear so frequently, and end up defeated (almost) every time, the Daleks are no longer a credible, or even entertaining, threat. We know that, whatever happens, they'll return sooner or later, only to once again be defeated at the last minute. Things have only been made worse by a few highly questionable ideas introduced in the name of keeping the monsters exciting. As if the human Dalek introduced in Daleks In Manhattan wasn't bad enough, the Power Rangers inspired multi-coloured versions introduced in Victory of the Daleks nearly ruined the characters once and for all. Fortunately, Stephen Moffat seems to have cottoned on to this fact, and has been using them as sparingly as possible. And to be fair, there's probably something in the BBC charter that says that the Daleks have to put in an appearance every dozen episodes or London will be destroyed by an fifty-foot tall inter-dimensional pigeon.