I expected Rex Tillerson was not going to stay long in the job of Secretary of State. He was seething with frustration in dealing with Trump soon after he was appointed and i thought he might quit on his own after staying a year or so for appearance sake.
Let's face it, Trump and Tillerson are radically different personalities and come from radically different backgrounds. Tillerson is the methodical, formal, conventional, Midwest engineer. Trump is the spontaneous, iconoclastic, quirky, NYC promoter. Tillerson rose through the bureacracy of Big Oil, Trump through the brutal, entrepreneurial culture of NY Real Estate Development. But still good management should be able to thrive of complementary styles.. but this might have been just too adversarial.
They were both 'big personalities' who craved space and independence to manoever. Frankly the Exec Branch might not have been big enough for both of them. Trump will always want to be the only Alpha Male in the room.
I also think there was a mutual incomprehension on policy. Tillerson was no economic nationalist. He came from a global corporation and made his bones negotiating contracts with world governments. I don't think they ever got on the same page in terms of a policy vision.
That said i profoundly dislike the way Trump does business. You should not fire someone on Twitter with no heads up. The same thing happened with FBI Director Comey. You meet one on one, lay out your case, let the target vent, thank him for his service, wish him well and work out a joint statement acceptable to both.
Even in New York City i don't think Trump's method is acceptable etiquette. It makes Trump look like a spoiled rich kid who was never taught proper manners. And franky.. it lacks CLASS.