“It was challenging for me coming from the disciplined, highly process-oriented ExxonMobil Corporation to go to work for a man who is pretty undisciplined, doesn’t — doesn’t like to read, doesn’t read briefing reports, doesn’t — doesn’t like to get into the details of a lot of things but rather just kind of says, look, this is what I believe and you can try to convince me otherwise, but most of the time you’re not going to do that.”…

“When the president would say, ‘Here’s what I want to do, and here’s how I want to do it,’ and I’d have to say to him, ‘Well, Mr. President, I understand what you want to do but you can’t do it that way. It violates the law, it violates the treaty, you know,’” Tillerson explained.

“I didn’t know how to conduct my affairs with him any other way than in a very straightforward fashion. And I think he grew tired of me being the guy every day that told him ‘You can’t do that, and let’s talk about what we can do.’”