With Mr. Iwata's recent passing, I have been reading about some of the excellent contributions he made to the games industry. One of the most interesting is this postmortem discussion he had with Shigesato Itoi and Shigeru Miyamoto. It's pretty long, but it's easily the most honest and humble postmortem document I have ever read. I highly suggest setting aside the time and reading through it.
Earthbound 64 Cancellation Discussion