Heartbroken..former Yahoo CEO Carol Bartz
Bartz reveals that she received the call from Bostock in New York on Tuesday evening and he read a prepared statement from a solicitor. Ivan Adnan

Yahoo's summary firing of CEO Carol Bartz knocked out one of the most visible women CEOs but also showed a phenomenon called the glass cliff, a technology professional women's association said.

Different from the glass ceiling that women complain have kept them out of executive suites and the U.S. Presidency, the glass cliff is a subtle form of gender bias that sets women up to fail, Jenny Slade, of the National Center for Women & Information Technology, told IBTimes.

Bartz, 63, was a computer scientist who'd had a stellar career at Autodesk, the architectural software developer, and Sun Microsystems before she was recruited to Yahoo in late 2008. One reason was that the Sunnyvale, Calif.-based search engine and advertising portal had foundered under its second and third male CEOs, most recently co-founder Jerry Yang.

When a company traditionally led by men is in trouble, Slade said, people are more likely to choose a woman to lead it. If the company is flourishing, people are more likely to stick with the male leadership status quo.

In a separate interview, global brands specialist Clive Chajet said Yahoo had blundered by publicly firing Bartz at a time when its brand has been damaged.

When you're firing a CEO, especially a female CEO, that's news quite separate from the value of the company itself, he told IBTimes. Yahoo, which was once the most attractive site on the Web, has lost share and needs to rebuild its brand.

The damage done has already triggered Third Point Advisors to acquire a 5.1 percent stake in the company. Before Bartz's tenure, activist Carl Icahn also took a large Yahoo stake and demanded a shakeup. He sold out after Bartz came in, during which the share price rose only 82 cents in nearly three years.

A week from now, nobody will ask, 'Who's Bartz? Or who's Fiorina?' Chajet continued, also recalling the 2005 firing of Carly Fiorina of troubled HP. Whether or not Bartz should have been fired is an internal issue and has nothing to do with the brand itself.

Chajet, now an independent consultant, was former head of Lippincott & Margulies, where he helped companies like AT&T and United Airlines deal with branding issues.

In an interview with Fortune on Thursday, Bartz claimed she was poorly treated by Yahoo Chairman Roy Bostock, whom she claimed didn't have the balls to tell me yourself about her firing. Then she blasted the Yahoo board, which includes two other women, as doofusses.

The National Center for Women in Technology, based at the University of Colorado, is a national coalition that seeks to promote women in the sector to provide diversity and a more competitive workforce. Its research shows that women hold only about 25 percent of U.S. technology jobs compared with 56 percent of all professional jobs.

Other research demonstrates the gradual falloff in women in technology that seems to begin in college programs in computer science and engineering and drops even more sharply in the technology workforce.

Slade said the glass cliff was first written about by psychologists Suzanne Bruckmiller and Nyla Branscombe in Harvard Business Review in 2001. They polled students about an organic food company company and supermarket chain seeking a new CEO.

The students picked men when the company was performing well and a woman when it was not. Only if male leaders have maneuvered an organization into trouble is a switch to a female leader preferred, the researchers concluded.

They also found that corporate boards had a history of gender bias but that once a woman CEO had performed well, they had little trouble hiring another.

One of the best examples of that phenomenon, is Xerox, where the board promoted Anne Mulcahy, a senior executive, to CEO in 2001 when the company was in trouble, then promoted Ursula Burns, a mechanical engineer, as her successor in 2009.

Next week, Telle Whitney, a NCWIT co-founder and noted computer scientist, is scheduled to appear alongside Secretary of State Hillary Clinton at the Asia- Pacific Economic Cooperation (APEC) Women in the Economy Summit. Other women from technology on the roster include Weili Dai, co-founder of Marvell Technology, and Marissa Mayer, VP of Google.

Yahoo shares were unchanged at $14.44 in morning Friday trading.