Sheryl Sandberg's warning to Hillary Clinton: 'They will have no empathy for you'

In her much-anticipated post-election volume, "What Happened," Hillary Rodham Clinton brings readers backstage at the tumultuous 2016 presidential campaign, sharing snapshots from the brutal race against now-President Donald Trump and revealing what she learned from the loss.

In one chapter, she recalls a particularly ominous conversation she had with Facebook COO Sheryl Sandberg, who Clinton describes as a personal friend. In a conversation at the outset of Clinton's campaign, Sandberg warned her it wasn't just her opponent, but the general public, from whom she'd face brutal criticism.

"They will have no empathy for you," Clinton recalls Sandberg saying.

The pair discussed obstacles they had faced as women in leadership roles, and two key points struck a chord with Clinton as she embarked on a campaign that would test her personal and professional strength.

"[Sandberg] told me that if there was one thing she wanted everyone to know from her book, it's this: The data show that for men, likability and professional success are correlated," Clinton writes.

In other words, the more successful a man is, the more people like him. The more successful a woman is, on the other hand, the less people like her.

"Hearing it put that simply," Clinton writes, "with data behind it, felt like a light bulb turning on."

One Harvard University study, for example, found that high-powered women incurred "backlash" if they spoke more than others in a group. A separate experiment within that same study found that high-powered women who speak longer than others in a group other are viewed as "incompetent and unsuitable for leadership."

Other research found that men feel threatened by women in leadership roles.

Sociologists at the Clayman Institute for Gender Research at Stanford University qualify this by saying, "to be clear, it is not that women are always disliked more than men when they are successful, but that they are often penalized when they behave in ways that violate gender stereotypes."

Clinton writes, that she and Sandberg also discussed "that women are seen favorably when they advocate for others, but unfavorably when they advocate for themselves."

The former Secretary of State says she felt that people liked her — so long as she was in a supportive role as First Lady or as a member of President Barack Obama's cabinet. The idea that women are embraced when they embrace the group is a concept Sandberg explores in "Lean In."

"As silly as it sounds, pronouns matter," she writes, recommending women use inclusive language, for example saying, "We had a great year," instead of "I had a great year."

Professor Hannah Riley Bowles, who studies gender and negotiations at Harvard's Kennedy School of Government, says that to negotiate successfully, women have to "come across as being nice" and be "concerned about others."

But even if a woman carefully follows the road map to corporate likability, she can still pay a price as she rises — a point that Clinton takes pains to underscore. Research shows that when a woman asks for a raise, she risks appearing greedy, demanding or unkind.

"Even if she gets a salary bump, she'll use a measure of goodwill," Clinton writes.

The Facebook COO told Clinton that she had "a steep mountain to climb" and after a turbulent and unsuccessful campaign, Sandberg's words ring true. Politics aside, sexism in the workplace is still an issue that affects women at every rung of the ladder.

"We've got to do better," Clinton writes. "Every single one of us."

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