In a conference call with analysts, she added: “It is going to be very busy.”

Very busy, and very riveting. Whether the intense, glamorous and controversial executive will get more time to fix the company promises to be one of Silicon Valley’s most prominent dramas of 2016. The next move is up to activist investors, who can try to elect a new slate to the Yahoo board.

The company said on Tuesday that one of its directors, Charles Schwab, was resigning because of other demands on his time.

Whether it is sold or survives, Yahoo is getting smaller. It said on Tuesday it would lay off about 15 percent of its 11,000 employees. By the end of the cuts, the company said its work force would be about 42 percent smaller than it was in 2012.

In addition to being smaller, Ms. Mayer said, the company would be simpler. Yahoo will shed assets, cut expenses and focus on the areas of the company that are growing. When she arrived at Yahoo after working as an executive at Google, she said, “We were sitting on $5 billion in deteriorating revenue with no clear path to growth.”

In essence, she said that Yahoo was no longer deteriorating and was poised for better times — not in 2016, perhaps, but 2017.