People look for predictable behavior, which gives them a sense of control. If you are deliberately unpredictable, it will keep people off-balance and they will wear themselves out trying to figure you out.

This is more of a tool for the master to maintain power. In The Devil Wears Prada, Meryl Streep's character is the head of a fashion magazine who strikes fear into the hearts of all who work there. Her excessive demands and cutting remarks keep everyone in suspended terror. And in return, she has power and control over those around her.

Alternatively, when you are on the rise to power, it's usually wiser to make your superiors more comfortable by being predictable. But as an underdog, however, you can make being unpredictable work for you. For example in Ted Lasso, the main character is relentlessly positive and unexpected in the way he treats people. Eventually as a result, he's able to win hearts and minds.

So I work in fashion and have encountered several unpredictable personalities. But one woman stands out as mastering this law.

She was nice...until she wasn't. Most of our interactions had to do with me getting her sign-off on something. So I spent hours preparing for each encounter, getting all the answers to potential questions. You never knew if you'd be received with good humor or extreme annoyance. Or whether the answer would enable you to do your job, or cause you to spin around in circles.

But, she had everyone wrapped around her finger. For people into fashion, her clothes were aspirational; high-end outfits that were effortlessly chic. I noticed that people would emulate her style. Her assistant even got the very same haircut one day. When she would tactfully cut someone down in a meeting, people were so caught off guard, I never once heard a good rebuttal. She had an equal title as my male boss, but somehow the power dynamic seemed very much tipped in her favor.

I could only stand back and admire her power. Being unpredictable has to be part of the whole package, but played right, this law enhances power.