Google hired Mayer straight out of Stanford and she helped to build many of its most famous features, including AdWords, Google Image Search, and Gmail. She made such a name for herself as a brilliant mind and hard worker that in 2012, after 13 years working for Google, Yahoo offered her the CEO position in hopes she'd be able turn around the fading tech company.
Sadly, Mayer's brilliance couldn't save Yahoo. She was also followed by Sillicon Valley sexism. A well-documented workaholic, she was criticized in 2015 for taking only two weeks of maternity leave after having a child. An article published by Forbes at the time of her hiring read:
Only 37, Mayer is young, pretty, vivacious – and the embodiment of the fresh start Yahoo needs.
Mayer was also criticized for her harsh managerial style, high-profile hacks that revealed billions of user's personal information to nefarious entities, and in-house privacy breaches at the request of the U.S. government. Amidst these scandals, it's not surprising Yahoo never managed to reach the heights Mayer aspired to.