He said there was a lot of backstabbing and unwelcome politics that went along with the role. No matter how good a role is, if you don't like the people, then it's fair enough I suppose. Eccleston's series was the one I found most enjoyable, even if looking back it contained a lot of cheese! Tennent's series has the most potential to be watched again and again such is the quality, whereas I stopped watching Smith after his first series. I think the series took a sharp downturn for me at least, when Billie Piper left and Catherine Tate/Martha were brought in.