I think there's plenty to make a case that Mayer specifically was a large negative vs Yahoo on twin-earth where someone else was CEO.
Many(?) aquisitions were her plan. From the article:
> goodwill impairment charges of $1.2 billion
This means since 2012 Mayer has overseen the aquisition of companies for at least $1.2b more than their book-value worth, and now that value is gone. Paid a premium for brands and then lost the value of those brands.
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> “She believes she can figure it out on her own,” says a former top Yahoo exec. “Her attitude is, ‘I watch TV shows, so I know TV shows.’” Mayer hired Katie Couric — in a deal reportedly worth up to $10 million per year, mostly in stock — because she personally likes the former TV news personality, without a sense of where and how Couric’s brand would appeal to Yahoo’s user base
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> Mayer was gung-ho on expanding Yahoo’s media business, particularly in video entertainment, approving a Netflix-like slate of scripted original series with a seven-year business plan to recoup the investment
> Yahoo formally exited TV-style entertainment in the third quarter of 2015, taking a $42 million write-down on [original series, deals, then axed Yahoo Screen division]
Her plan.
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> Yahoo in February folded seven digital magazines, including titles covering food and travel, which had been a Mayer pet project. She wanted to launch dozens of vertically oriented magazines, dictating that they use Tumblr-based designs, hoping to better monetize Yahoo’s monthly audience.
Her plan.
> Mayer has positioned those closures as a refocusing on Yahoo’s four strongest content segments — news, sports, finance, and lifestyle — as the company aims to cut 15% of its workforce over the course of 2016. But those were the areas on which Yahoo should have stayed laser-focused all along, according to S&P’s Kessler.
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She had ideas that were either unworkable, poorly implemented, or she was unknowledgeable and hired the wrong people.
> I don't think the failure is on Mayer
That's how this works. She had a job and failed. It's okay to say that. They aren't paying her to not take responsibility. They will be paying her more than you and I and many readers of this comment combined may ever make, just to leave.