You are probably as fatigued as I am about this topic: Why the hell are women still lagging behind men at law firms? (Though women have constituted about 50 percent of law students since the mid-1990s, they are barely 19 percent of partners in major firms.)

For at least a dozen years, I've looked for explanations: Is it simple sexism? Is it the dearth of role models/mentors? Could it be the clash of work and family? Are women too complacent/bitchy? Are they wearing the wrong shoes?

My assumption has been that women want the brass ring of partnership, but that they hit hurdles along the way. What I haven't explored as much is this: Maybe women aren't that interested. I've seen that lack of interest not only from women on the ascent, but also from those who've attained partnership and want out.

Simply put, women aren't enamored with Big Law, and they're bolting. While women are well-represented in the junior classes at firms, they leave in greater numbers as they move up in seniority. According to the American Bar Association, women over the age of 40 represent just 41 percent of lawyers at law firms, and that dips to 27 percent for women over 50.

Are women dropping out because law firms are still boys clubs in which they feel out of place? Or is it something else entirely—such as a different conception of a satisfying career? 

The distinction can be fuzzy. "It's difficult to say, but I think the two go hand in hand," says Kate Hooker, a former Cadwalader Wickersham & Taft associate who's now senior counsel at a start-up. Besides the relentless hours, Hooker adds, "there were so few women in leadership that I didn't see what my own path would be."

Women are keeping their eyes open for other gigs. "There are several pivotal moments," says career coach Elena Duetch, who runs Women Interested in Leaving Law. She says women tend to explore their options "after the third-year, when they start to say, this isn't for me; and at the seventh or eighth year, when they're seasoned but still young enough to try something new." And those moments continue, she says: "Women in their 50s see 20 years ahead of them and want to do something with more meaning."

It doesn't help that firms are sometimes turning young women off, even when they think they're helping them stay on. Alix Devendra, who graduated first in her class from Case Western Reserve Law School in 2011, says she had every intention of returning to work at Nixon Peabody in San Francisco after her pregnancy. After the firm encouraged her to go on an 80 percent schedule, she was shocked that it put her on notice a month later that she wasn't reaching her mark. She quit the next day. "I didn't like the tone, subtext, culture," she says. "The hypocrisy of saying we’ll support you, then turning around and saying, you didn’t reach 80 percent—that was the last straw." 

"We were incredibly disappointed to see her leave," says Stacie Collier, an employment partner at the firm who supervised Devendra. "We tried to help her, and I’m sorry that she didn't feel supported. She was someone we wanted to retain—high potential and really smart."

Some women leave because they find partnership not worth the price. Despite getting all the right signals that she was likely to make partner, one former associate at a big Los Angeles firm quit in her eighth year. "I worked all the time," she says. "If I had seen a path to a reasonable lifestyle, I might have stayed." Though she voices regret that she quit too quickly (she took a "boring" government job that she later left), she says she had burned out on firm life: "I'm good at my job but I didn't find meaning in it."

Indeed, "meaning" is what women often say they want—and what's lacking in Big Law.

"I've been doing this for 20 years, and I'm doing it at a very high level, but is this what I want to do for the next 20?" asks a female partner at an Am Law 100 firm? "What's so rewarding about slaving away for clients who think they own you?"

What's rewarding to men is often the money. Whether it's because men are usually the primary breadwinner or they measure their worth by what they make, money seems to have a distinctly masculine appeal. In contrast, "meaning is a primary driver for many women," says law firm consultant Melissa McClenaghan Martin. 

So if money is not the big draw for women, what will keep them in Big Law? It's a a cliche, but women value relationships. "Women who have found meaning, reward in their work, do so through business development, and deep client or sponsor relationships," says Martin, a former Fried Frank associate.

The problem, though, is that it's tougher for women to develop those relationships than men. "I know plenty of high achieving women who—like me—began their careers with expectations of partnership but somewhere along the way they took themselves off track," says Martin. "It happens because there are more reasons for women to opt out than there are to opt in." 

And the system isn't doing much to change their minds.