Former first lady Michelle Obama speaks during a stop on her book tour at Brooklyn's Barclays Center on Dec. 1. (Mary Altaffer/AP)

When former first lady Michelle Obama mentioned how “leaning in,” an approach popularized by Facebook executive Sheryl Sandberg, doesn’t always work, she was largely met with praise from women who agreed and were thrilled by her candor.

Speaking about the challenges of balancing home life with a career to a packed audience Saturday at the Barclays Center in Brooklyn, Obama reportedly said: “Marriage still ain’t equal, y’all. It ain’t equal. I tell women that whole ‘you can have it all’ — mmm, nope. Not at the same time — that’s a lie. It’s not always enough to lean in, because that s--- doesn’t work.”

The rejection of the “lean-in” approach by one of the most influential black women in America resonated, especially among black women.

“Leaning in” entered the national conversation in 2013 after being mentioned in Sandberg’s book “Lean In: Women, Work, and the Will to Lead.” The Washington Post’s Allyson Chiu wrote that the book “encouraged women to assert themselves at work and in their communities to avoid ending up in subordinate positions. The concept is linked to the ambitious idea that women, as long as they try, can simultaneously thrive in their personal lives and at work.”

But from the earliest days of the book’s publication, the concept received a lot of pushback. Some thought Sandberg’s approach came from a place of wealth and privilege that did not jibe with the reality of most women’s lives, especially women of color. Obama’s public dismissal of the concept affirmed what many women, particularly the black women who count themselves as some of her biggest supporters, have long known: combating sexism while climbing the career ladder and trying to balance family life is especially hard in a racist society.

Sharese Reyes, a mother and lawyer in Atlanta, told The Fix that she never bought into “leaning in,” because she recognized early that it was reminiscent of feminism as practiced by white women.

“I did not see a recognition of the additional challenges women of color face, especially in a corporate setting,” Reyes said. “When women of color, especially black women, ‘lean in,’ we get pushed back. Our assertiveness is deemed ‘lack of interpersonal skills’ or, worse, playing on the tired stereotype of the ‘angry black woman.’ I don’t like to play victim, but as Michelle so plainly stated, ‘That s--- doesn’t work!’

Erin Almond, a wife and mother who manages a college prep program in Jacksonville, Fla., said “leaning in” is challenging for women constantly trying to avoid being perceived as “the angry black woman.”

“In general, I think the lean-in philosophy ignores that there is an element of privilege required to be able to do so. To be able to lean in at work means that you are most often outsourcing other aspects of your life. . . . Considering that black women aren’t earning at the same rate as their counterparts, plus the burden of student loan debt [because additional education is often required of black women to be at the table in the first place] and other cultural elements of helping to take care of/support family members who are less well off, there just isn’t the space to lean in or the ability to do so when you’re stretched.”

And there certainly isn’t always space to lean in when you don’t have a partner to help support you — something Sandberg learned after the sudden death of her husband, Dave Goldberg. More than two-thirds of black working moms are not married, according to the Economic Policy Institute.

Balancing motherhood and career without a partner gave Sandberg a perspective she had not originally considered. She told USA Today last year:

I posted publicly on Mother's Day last year that I think I didn't fully appreciate what it was to be a single mother. I certainly wrote about it in Lean In but I also wrote a whole chapter called "Make Your Partner a Real Partner," which for people who didn't have one must have been very hard to read.

I have thought a lot about what it is to be a single mother because now I am one. And financially, I don’t face the struggles that so many do. Thirty-seven percent of single mothers are living in poverty, 40% if you are black or Latina. That’s unacceptable.

Wendy Osefo, an education professor at Johns Hopkins University, said there is a way to advocate the best parts of “leaning in” that also works better for women of color. “Change will only come from a top-down approach where employers are intentional in their efforts to advance the careers of black women,” Osefo said.

When one of the most powerful women in the world communicates that “leaning in” is a challenge, one can expect that black women with less privilege are enduring similar fates. Obama has the ear of those women, and of the decision-makers in Washington and elsewhere in America, so her words are a particularly important acknowledgment of the challenges that black women in America continue to face.