The job had been open for six months.

Beth Comstock knew the call would come — the one from human resources inviting her to take over as senior vice president of corporate communications at NBC.

But the call never came.

At the time, Comstock was in her twenties, working diligently as the vice president of news media relations at NBC. She told Business Insider that she’d gripe to her family, “I can’t believe they’re not considering me for that job!”

Eventually, Comstock was angry enough that she worked up the nerve to approach the head of HR. “You haven’t filled the job,” she recalled saying. “Why? I’d like to be considered.”

The response was jarring. “Well, that’s good to hear,” he said, according to Comstock. “We did consider you. We just assumed that because this job requires so much travel and you’re a young mother that it wouldn’t work for you.”

Comstock was recently divorced, with a toddler-age daughter — and this assessment of her potential was infuriating to her. But she said it taught her several lessons that shaped the rest of her career.

Comstock recounts this experience in her new book, “Imagine It Forward,” written with Tahl Raz. The book describes how Comstock progressed from an aspiring broadcast journalist to the vice chair of General Electric, becoming the first woman to hold that position. (Comstock left GE last year after nearly three decades there.)

“I was equal parts angry at him” — the head of HR — “and me at that moment,” Comstock said.

On the one hand, she thought, “Who are you to assume what my constraints are or aren’t?” On the other, she said, “I was mad at myself, because how would they know [I wanted the job] if I didn’t tell them?”

Ultimately, she landed the promotion.

Comstock learned to be open about her professional ambitions

Comstock said that the lesson she learned from that experience is: “You’re the boss of you. Until you tell people what you want to do, there’s no way you can do it.”

She vowed to herself that going forward she’d make her career ambitions clear and ask her manager to help her get there.

And when she began managing people, Comstock said, she knew to “never assume you know what someone wants to do or wants to take on, because circumstances change.”

These lessons line up with advice from HR experts like Toni Thompson, the vice president of people and talent at The Muse, whopreviously told Business Insider that it’s important to tell your boss exactly what you want in terms of title, salary, and opportunities.

“They may not be able to give it to you right away,” Thompson said. “But it’s really great if you have that conversation up front, because then they are able to tell you … are you ready for the role that you’re saying you’re ready for? And they’ll be able to keep an eye out for big assignments or responsibilities that they might be able to give to you.”

Only about half of employees do this, Thompson said.

As for Comstock, an additional perk of her speaking up was that she ended up forging a two-way mentorship with the head of HR — he became a coach to her, while she “helped coach him about what young mothers could do in organizations,” she said.

Originally published at businessinsider.com

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