This article (http://sports.espn.go.com/nba/news/story?id=3217276) on ESPN.com says that Skiles anticipated and advocated for his own firing, realizing that he wasn't getting through to his players.  Boylan assures us that Skiles did not "quit on the team."

Interesting tidbit: Reinsdorf reveals that either Gordon or Deng told him that not signing an extension was a mistake (he doesn't give the name).