Back in 2008, I was writing a book about teams and got to the chapter about team leadership. That's when I crafted a definition of leadership I liked (the four-dimensional definition). Then I developed a three-level model showing what leaders have to do to (a) address the four dimensions and (b) grow themselves as leaders.
That's when I thought, "Hold on, these models are pretty good." I checked on the Internet and realised they were original contributions to the field of leadership.
More thoughts and ideas flowed and pretty soon I realised there was a book on leadership trying to get born. So I abandoned the teams book and surrendered to the flow of ideas. Sounds odd, I know, but that's the way it was.