And then, even worse, getting rid of the daleks through what was literally a deus ex machina ending. I'm sorry but it was lame.
What about when Daniel Jackson evolved on Stargate SG1.
Or when Major Carter got taken over by a machine.
Or O'neill with the alien knowledge that let him control some wierd looking things that destroyed the Gu'auld fleet.
Or Captain Sisko becoming a profit on Star Trek: DS9.
Or what ever happened on Earth: Final Conflict (which I did not watch much of).

Sci-Fi is full of that type of thing happening.

And it is lame every time it happens.