You're going to love this one...

In his 2015 book, "Elon Musk: Tesla, SpaceX, and the Quest for a Fantastic Future," Ashlee Vance shares the story of how Musk stopped working with his longtime executive assistant in early 2014.

According to Vance, the assistant, Mary Beth Brown, asked Musk for a significant raise after she'd been working with him for 12 years. In response, Musk told Brown to take two weeks off, during which he would assume her responsibilities and see whether she was critical to his success.

When Brown returned, Musk told her he didn't need her anymore.  

Whoops.  

OK, couple of things.  While Musk generally is on the record as saying this book is accurate he strongly denies the reporting of this encounter.  Brown also denies the reporting that she lost her job through the rigid efficiency study conducted by Musk.  Also, after Brown was no longer in the role, Musk says he needed the position, as evidenced by the fact he hired 2-3 specialists (PR, etc.) rather than a generalist executive assistant.

Still, where there's smoke, there's fire.  My take is that Musk probably did consider whether the position still worked for him based on the way his business has changed.

Add this to the list of things to be careful asking for.  The most common error employees make is taking an offer to their boss expecting a counteroffer.  The boss, rather than countering, wishes the employee luck in the new position.

Want a raise?  Interesting.  How about you take a couple of days off while I determine how vital you are to the organization?

Elon Musk.  The most interesting man in the world.