Marissa Mayer's employer is the board of directors of Yahoo. Their bosses are shareholders, who want to make money. That's the metric by which she is evaluated.

Marissa Mayer's employer is the board of directors of Yahoo. Their bosses are shareholders, who want to make money. That's the metric by which she is evaluated. YHOO was trading around $16 per share when she started at the company. Today it's hovering around $37, for a gain of ~130% over 4 years. That's an annualized rate of return of 24%, which handily beats the indexes over that period. You may not like her, or her decisions, but it's simply not true that male bosses are usually fired for this kind of performance. Edit: yadda yadda of course the stock benefits from the decisions of her predecessors. They also made the job harder for her in other ways. But: stock performance during their tenure is the #1 way CEOs are evaluated.