They're also often brutally honest. I read many postmortems of games that failed, either commercially and/or in respect to their original vision, and the postmo

They're also often brutally honest. I read many postmortems of games that failed, either commercially and/or in respect to their original vision, and the postmortem explored the how and why of that more than "what we learned from this and how this will make our next product more awesome". A postmortem is best when it's clinical and conducted under an unblinking neon light, and some of the ones on Gamasutra are truly something to aspire to. They're written by and for developers, they're not marketing, I love that.