The sale of Yahoo to Verizon for $4.83bn (£3.62bn) marks the end of a period of intense speculation and ferocious investor activism at the embattled web company. And for the past four years, CEO Marissa Mayer has borne the brunt of that protest, while attempting to turn around Yahoo’s fortunes.

Yahoo’s years-long profits slump was made worse by bad investments that came to a head at the beginning of 2016, when the company reported a $4.4bn loss. Expensive gambles, such as the $1.1bn acquisition of Tumblr in 2013, came to epitomize Mayer’s bold but ultimately doomed attempt to reinvent Yahoo as a media platform that would attract younger users and turn the company’s fortunes around.

Some of the firm’s increasingly rancorous investors had consistently complained about Mayer’s leadership, and in March 2016, some at Starboard Value, an investor in the company, called for the entire board to be replaced.

Mayer’s hiring in July 2012 was heralded as a coup for the struggling company. Yahoo was in a state of turmoil at the time, having run through four chief executives in the previous four years. Mayer had been poached from a high-profile role at Google, where she had been the 20th employee and was credited with key contributions to many of the company’s most important products.

Announcing the Verizon deal on Monday, Mayer said in a Tumblr post: “For me personally, I’m planning to stay. I love Yahoo, and I believe in all of you. It’s important to me to see Yahoo into its next chapter.”

Yet Marni Walden, Verizon’s executive vice-president who masterminded the deal, told CNBC that the leadership had not yet been decided. Mayer’s departure is now viewed as all but inevitable, as she is held responsible for failing to produce Yahoo’s ever-promised turnaround and a valuation of its core business that at one point fell to negative $13bn.

That crisis prompted another round of discussion of the decade-old question: what is Yahoo?

Identity crisis

That question has dogged the company since long before Mayer took charge, but despite the optimism that marked the beginning of her tenure, the 40-year-old executive failed to provide a coherent answer. Mayer’s much-vaunted initiative to rebrand Yahoo – 2013’s “30 Days of Change” – may as well have swapped out the company’s irritating exclamation point for a question mark.

Yahoo’s identity crisis was baked into the pie. Founded in 1994 by Jerry Yang and David Filo, two Stanford graduate students, “Jerry and David’s guide to the World Wide Web” was a simple list of links to other websites, arranged by categories. The web portal was an accessible entry point for novice internet users, but the hodgepodge nature of the company – which changed its name to Yahoo! within a few months of launching – has persisted.

The advertising world has declined to take Yahoo seriously for a while now. Brian Wieser, an analyst with Pivotal Research group and formerly head forecaster at the ad agency Magna Global, said that Yahoo had consistently failed to distinguish itself from other companies claiming to provide “premium” material to visitors.

“Yahoo is a notional premium publisher,” Wieser said – it has a recognizable brand name, but not one that’s worth anything. “They have no coherent appreciation of the advertising business.” Wieser’s appraisal is reflected in the company’s finances: its revenues dipped some $300m in 2015.

Today, a visit to maintains in many ways the feel of the original site: Here is the entire world wide web, sort of. Yahoo has its own version of almost everything a casual internet user might want – email, photo sharing, movie times, news aggregation and social media. Yet everything Yahoo can do, someone else can do better, and they do. It’s hard to pinpoint a single area where Yahoo outperforms another website or app. Millions of aging users may still rely on Yahoo Mail or Yahoo News, but the younger and more sophisticated masses have moved on.

One telling – if somewhat poignant – example of Yahoo’s inherent un-hipness is its “Makers” vertical. While to most Silicon Valley types, that buzzword refers to those enterprising tinkerers trying to build a better drone in their garage, Yahoo! Makers is a Pinterest-lite page dedicated to domestic DIY projects such as turning a straw hat and industrial light bulb into a “surprising pendant light project”.

Making sense of Yahoo’s mishmash was a tall order for Mayer. The Guardian described the Yahoo CEO role as a “poisoned chalice” in 2012, and her two predecessors were perhaps known as much for how they left the company (one in a storm of profanity after being canned by the board of directors over the phone; another in disgrace after it was revealed that he lied on his resume) as for anything they achieved at the helm.

Mayer was already a star when she became one of the few female CEOs in Silicon Valley after a protracted contest with interim CEO Ross Levinsohn that ended – apparently to his surprise – in his ousting. Unbeknownst to Levinsohn, Mayer had several members of the board, notably billionaire Dan Loeb, on her side. Loeb abruptly cashed out in 2013.

During her thirteen years at Google, the computer scientist (with a specialism in artificial intelligence) was a member of the three-person team that invented Google AdWords, the algorithm that remains Google’s chief source of revenue. “It’s pretty hard to overstate her impact,” Alphabet’s Eric Schmidt told Glamour in 2009. “She built the team that designs the products we all use.”

Mayer has a reputation for her intellect, limitless work ethic and commitment to making decisions based on scientific evidence. She is known for settling a dispute over the color of Google’s hyperlinks by creating a randomized test for users with 40 shades of blue. The shade that earned the most clicks won.

A promising start

Yahoo’s first set of financial results after Mayer’s installation as CEO reflected the optimism that accompanied her appointment, and her first major moves – the $1.1bn acquisition of blogging platform Tumblr and long-desired upgrade of photo-sharing service Flickr – impressed the industry. Tumblr promised growth with younger users while Flickr represented one of Yahoo’s flagship successes that had languished due to a lack of investment.

In July 2013, Yahoo outperformed Google for the first time in two years.

“No online media outlet would have come close to predicting this, and if they had, you would have said they were insane,” one analyst said at the time. “This will probably have a positive impact on the share price and if Yahoo keeps this up, it has a chance of becoming relevant again.”

Still, despite the early indications of a turnaround, Mayer’s elevation also opened up her personality and management style to increased scrutiny, and much of it wasn’t pretty. Her decision to take just two weeks maternity leave after the birth of her twins garnered some criticism, though it’s hard to imagine that any choice she made would have gone un-snarked.

More significant were reports in January 2013 that Mayer was consistently late for meetings – a bad habit that subordinates felt indicated a lack of respect for their time. In February 2013, the CEO barred the company’s 11,500 employees from working from home, angering many employees and reigniting a national debate about the benefits of remote work that left Mayer pegged as unempathetic, unfeminist and unenvironmental. The next month brought a report that Mayer was micromanaging the hiring process, to the detriment of the company’s ability to recruit top talent.

Mayer’s stalled ascension at Google – where she had been demoted laterally to local products in 2010 – started to make more sense.

A shaky strategy

Mayer unveiled a new sort of strategy in early 2014, when she launched a series of digital magazines in an attempt to reposition Yahoo as a media company. Hiring journalistic heavy hitters like Katie Couric and David Pogue gave the announcement a veneer of verisimilitude, but consumers, advertisers, and the stock market remained unconvinced.

By the time Yahoo’s most valuable investment, the Chinese internet company Alibaba, went public in September 2014,

Yahoo was forced to differentiate its own value from Alibaba’s, and was again searching for the answer to the question: “What is Yahoo’s core business?” As she moves forward, Mayer may well be asking the same question of herself.

This article was written by Julia Carrie Wong in San Francisco and Sam Thielman in New York, for on Tuesday 26th July 2016 12.00 Europe/London © Guardian News and Media Limited 2010