On Sept. 1, General Electric announced that Beth Comstock would became the first female vice chair in the history of the industrial giant. She joined a trio of GE men who also hold that top executive title, including the head of global operations, the CEO of the company's finance unit, and the service and operations chief. After more than a decade as GE's marketing chief, Comstock is now charged with leading the company's new growth efforts and running its historic lighting business.

So it was fitting to sit down with Comstock at Fortune's Most Powerful Women Summit in Washington for a conversation about her career. She opened up about how having self-confidence has always been "vexing" for her, and how she's learned to interpret "no" as "not yet." The conversation below has been edited for length and clarity.

Q. What does it mean to you to be the first female vice chair of GE?

A. I’ve been at GE pretty much the bulk of my career. I grew up on the NBC side and transitioned over to GE, so for me the vice chair role is sort of a way to express the fact that I’ve been there a long time. But it also helps prove that the mandate we’re driving—growth and innovation—matters in the company. If anything it gives me a bit more urgency that we’ve got to make sure that these efforts stick.

Q. What's one of the most critical leadership lessons you’ve learned over the course of your career? 

A. GE is very big on personal development. I think that’s why I’ve stayed at the company so long. It’s a company that expects you to continually develop yourself.

One of the things the company does is these 360-degree evaluations. One that I went through was so exhaustive: I felt like I was going in for White House security clearance or something. They went all the way back to my high school and talked to dozens of people about me, so it was a very comprehensive set of insights.

It wasn’t all glowing. One of the pieces of feedback I got was: Slow down. You don’t have to have all the answers. You need to ask for help. You come into every meeting and to every interaction having thought through everything, and want it all wrapped in a little bow: “Here’s the idea and let’s go.” Well, it doesn’t work that way. People want to be part of the process. They want to be part of the discovery and coming up with the ideas. They want to help.

It was just such an awakening. It made me realize that in general, in my personal and professional life, I was afraid to ask for help. I felt like, "I have to do it myself. I’ve got to soldier through this." The reality is when you ask for help, ideas get better and projects become easier, even fun.

Q. Tell us about a time when you put that to work recently.

A. In innovation today in companies, the problems that we’re trying to solve are too big. You can’t do it alone. Last week, we launched a new energy business called Current that combines some things like our LED business and solar. But we had an advisory board where we went to some great experts before we launched and said, “Help us make this better.”

I’ve tried to make that the way I work with any endeavor: Ask somebody else. We’ve done a lot in the company with open innovation—this idea that maybe all the best ideas don’t actually reside in your company.

Q. Speaking of speaking up, I’ve read that CEO Jeff Immelt gave you advice much earlier in your career to be more confident.

A. Confidence is something I’ve struggled with for most of my career. I don’t know why. I was raised in a great town with a great family and parents who really encouraged me. But confidence has been vexing for me. You can fake-it-til-you-make-it only so much.

I remember once I was in a meeting, and afterwards Jeff Immelt said, “I need to talk to you.” He said, "Look, you've just got to put it out there more. I mean, why aren’t you being more confident in these situations?” And I was kind of like: The gig is up. He figured me out. I thought I was acting pretty well.

But it was helpful to me. It was him saying, “Look, I need you to voice your opinion. You’re here for a reason, and it doesn’t do the company good, and it doesn’t do you good.”

I think that’s a lesson. You need to make sure you have people who have your back, and that they're willing to say these things. For me, building confidence has been about putting yourself out there in a little way. Maybe it doesn’t always go well, but it’s not a big risk. Then you feel more confident if it goes well, and you’re willing to take a bigger risk the next time. So that's how I’ve gone about building my confidence: Just trying little things, and when they go well, challenging myself to do the next thing.

Q. How critical was that to you, to have Jeff tell you "it's okay to do this" and encourage it?

A. It was very important to have my boss say, “Hey, you've got to show up more.” It’s an important message. He could have just written it off and said, "I’m not going to assign her to the next thing, because if she’s not confident enough, how can she do this?" Clearly he saw something and wanted to make it better.

I think leaders need to do that. You help the people who work with you be better. I try to emulate that with teams I work on. You don’t need to do it in a big setting when everyone’s sitting around the table, but find a way with a specific project to give specific feedback.

Q. What’s been one of the biggest keys to your success?

A. I think one is just curiosity—wanting to learn and to constantly try to be better and do better. But to me it all boils down to just not giving up. Sometimes I think in business, in our careers, we all want to rally around the big launch, the big project, the resume that has all the accomplishments.

But really it is that everyday you're going in and keeping at it. There are so many times when we’ve all thought, "I’m done with this." And there are times when you do need to be done. But for things that you really are passionate about, find a way to keep going. I don’t take no easily or lightly. No basically means "not yet." I’m going to keep working it until I get to yes.

Read also:

Five great pieces of advice from Fortune’s Most Powerful Women

This year’s Most Powerful Women ranking hits a milestone

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