No matter what profession a woman works in, she's actually in the service profession.

That's the upshot of an illuminating (and to many, enraging) new Columbia Business School study highlighted this week, showing that co-workers and bosses feel entitled to favors from women – or, in fact, that almost everything a woman does at work is considered "a favor" that is off the clock. To put it another way, when a woman takes on a project no one else will, or does something helpful or thoughtful, it's seen as something she does for fun. When a man does it, it seen as real work.

The revelation of this structural ingratitude explains a lot. It's a pivotal point in understanding a key issue in workplaces: why can't women form lasting alliances, even though they spend more time contributing to their organizations by mentoring?

Alliances are often based on favors; if a favor is not counted, a potential ally is lost.

Why is it that women are often thought to lack "executive presence", which is the aura of accomplishment and authority that hovers around powerful people? Why are men 46% more likely to have "sponsors" boost their rise through an organization? It all comes down to the fact that women are essentially locked out of the favor system that helps men get ahead; many powerful men keep a running tally in their heads of who owes them a favor and who doesn't; women, because their favors don't count, never even make it on to that list. Favors are a currency, and women are suffering from a currency crisis.

That ends up leaving many powerful women on shaky ground, easily scapegoated when something goes wrong. It's a fear that most women learn to live with, and be wary of, as they rise through the ranks. The higher the woman's rise, the greater her wariness, which is probably why, as a reporter and editor, I find many female entrepreneurs and executives shunning the spotlight of news when they're succeeding, while male executives tend to court news coverage.

A few years ago, I interviewed a prominent woman and financial executive about how she had made it so far in a male-dominated profession. With her public relations advisor on the line, she sang the praises of her "supportive" coworkers and bosses and took barely any credit for her own talent and resilience. I was baffled, but after years of covering Wall Street, I was used to women avoiding the spotlight and shuffling off responsibility for success to others. This time, I understood why. After we hung up, she called me back, alone, to check that she had not misspoken about something. She told me:

I have to be very careful. This place is a shark tank, and there are a lot of people who'd love to use something against me.

It's a realization that many women in male-dominated professions – particularly Wall Street – have long understood: one wrong step, and they suffer far harsher consequences than men in similar positions. It's part of the reason women don't rise very far, and why, when push comes to shove, it's women who get laid off (layoffs also disproportionately hurt minorities); as Anita Raghavan noted in Forbes:

72% of the people laid off on Wall Street after the financial crisis were women, even though they made up 64% of the workforce before the crisis.

This trend is also particularly apparent in another important aspect of women's careers: mentoring and networking. The standard advice for women who feel stuck is to seek a mentor, or to build an external network so that they can find information, support and advice outside their workplace.

Yet, this backfires too. When favors don't really count, women find themselves marginalized in professional networks as much as they do at work. Studies have shown that women in academia, for instance, find their own rise through the ranks slowed because they spend too much time helping or tutoring students. Professional women also spend a lot of time "mentoring down", which cuts down on the time they can spend talking to powerful people within their organizations.

Every woman has an anecdote of having her contacts, good will, or time being taken for granted. A friend who is a professor pronounced herself "mesmerized" by how the men in her department were rarely imposed upon by students, whereas she and other women were always being asked for extra help.

There was an example in my own life recently, most recently when a hiring manager at another publication asked me to scour my network to recommend a candidate for a prestigious job; later, neither the candidate nor the editor who asked for my help said "thank you".

I don't regret the time and effort it took to make the introduction, but that lack of acknowledgement concerned me, as it would concern others. The lack of acknowledgement is not just a matter of rudeness, ingratitude or bad manners; it's a rejection of a potential alliance. It means that, should a woman ever ask for a favor from the people she has done favors for, she might find that help is a one-way street. She would likely not receive any help, since her own work on their behalf was not acknowledged. She might behave as an ally, but she will find, according to the implications of this study, that others won't behave as hers.

It's the same predicament a lot of women find themselves in: women want to help, but their help doesn't seem to count. Feeling victimized will certainly not be productive, but the study, and commenters on it, offer precious little usable advice. Some suggest not doing as many favors, which, while it might reduce the problem of unappreciative recipients, won't actually solve it. Some suggest being a little more insistent on credit when doing a favor, which might work though it sounds exhausting; a favor is not a rug in a Moroccan souk where haggling is appropriate. Some suggest just getting used to being taken for granted, but women have had thousands of years to acclimate to that state of affairs, and it hasn't been terribly successful.

Ultimately, the solution is probably something a lot bigger. There are multiple ways that society places too little value on the contribution of women, then tells them they're not contributing enough. This is true when women who are mothers are called "housewives", as if their labor at home has no value. It's true when women at work are paid less. It's true when women are marginalized in any realm, from politics to medicine. It's worth everyone's time to think about how to change that. That seems to be a change that society considers a mere favor. It's actually going to be real work.