I read that after the evil of the Daleks, Terry Nation planned to make a American tv series staring the Daleks,does anyone know why it never took off?

Daleks can work pretty well as villains, especially when used sparingly.
As lead characters however they would be very very dull.
Frankly, Daleks simply aren't anything like as interesting as Terry Nation thought they were. And Daleks, throughout Who history, have always been better written by almost anyone other than Nation.
I've recently rewatched Planet Of The Daleks, and there's lots of Dalek on Dalek dialogue, which is so tedious. Imagine lots of Daleks chatting away on an American series? Thank goodness that never happened...

It was before Evil of the Daleks that Nation first tried getting a Dalek Spin Off. First with the BBC and then with NBC.


From here

I could see something working in the style of The Tripods, the efforts of a resistance movement in a world overrun by Daleks, but they've been portrayed as more and more overpowered over the years that it wouldn't be much of a fair fight.

I think this idea was based on the Dalek's appearances being so popular, rather than them being an actual fountain of ideas.

As said, Terry Nation was more than happy to commercialise the hell out of the Daleks at the expense of writing quality and integrity. I imagine the show would have been pretty hit-and-miss, so it's probably not much of loss.

I think that the old Abslom Daak - Dalek Killer comic strip would have some legs with a good update.

The Destroyers
http://tardis.wikia.com/wiki/The_Des...duced_spin-off)

I also remember stirrings around 1990 about some kind of Dalek spin-off, I think it was for an animated series geared for Children's BBC?
It prompted Mark Ayres to compose a theme for it to submit to the producers. The project was shelved but Mark released the theme anyway and put it on the extended CD version of his Myths and Other Legends album.

Big Finish produced a dalek empire series


https://www.bigfinish.com/ranges/rel...e/dalek-empire