Ever since she stormed into Yahoo as its new CEO in January, Carol Bartz has been adamant that the company needs to simplify and define itself. What is Yahoo? “We’re not a search company. We’re not just a social media company. We’re not just a content company. We’re really the center of people’s online lives,” she told Fortune managing editor Andy Serwer in an on-stage interview at the Fortune Most Powerful Women Summit earlier this month. Haunted by Google and handicapped by its failure to do a deal with Microsoft last year, Yahoo has finally gotten some mojo back now that Bartz has struck a search partnership with Microsoft and, just today, launched a $100 million-plus ad campaign. (It’s Y!ou)

Bartz, meanwhile, has never had much problem defining herself. For this year’s Fortune Most Powerful Women issue, the ever-candid and colorful CEO (No. 8 on the MPWomen list) wrote a first-personer explaining what’s made her who she is. We ran an edited version of Bartz’s first-personer in the magazine, but her piece was so good–and so Carol–that we want to share her unedited version in its entirety. After all, as everyone who knows her knows, the best Bartz is the unedited Bartz. So here’s Bartz on Bartz:

I have a lousy track record of starting a new job and then having major surgery. It’s certainly not planned, but people around me have made a lot about me returning to work quickly, which I find fascinating.

I’ve been at Yahoo! since January, and a few months back I had my knee replaced. I scheduled the surgery sooner rather than later, once my doctor identified the need. Why should I wait to feel good? I want to feel good NOW, rather than wait 10 more years. I want to just deal with it. I want to get moving.

I did the same thing with breast cancer surgery, which took place weeks after I became CEO of Autodesk . I was back in the office soon after that. It’s not because I wanted to be a martyr. It’s because I had a job to do, and my family knew I’d be much happier if I was back in the saddle. I love to work. I love to run companies. I love to help people I work with. And I don’t let anything get in the way of doing what I love.

Does my childhood have anything to do with this “just deal with it” approach? Possibly. There is something to growing up on a Midwest farm that encourages hard work. The farm won’t wait for a better mood. And neither did my grandmother who raised me. But I encourage everyone – and more and more women – to not take no for an answer if it’s between them and something they care passionately about. What are you waiting for?

Coming to California and Silicon Valley in particular was a blessing for me. I realized soon after arriving here that most people didn’t take a lot of time to ponder, or analyze a decision to death. There just isn’t time. This fit my impatient nature of “doing” very well, and my belief that it’s always worth spending energy on “doing” something better. The technology industry is a great environment for dynamic, innovative optimism.

Moving forward was just what Autodesk seemed to need when I arrived there in 1992. The company was full of brilliant engineers, but no one was making tough decisions and ensuring that projects and performance moved forward. Sometimes even the best of us need a kick in the pants. And making those difficult decisions requires the confidence to stand behind them, especially in a less-than supportive environment. It requires role-modeling the behavior you want your leaders to mimic. It means promoting cooperation, communicating and making sure everyone is responsible for making things happen. Asking everyone to face their fears and get moving!

I like change. Frankly, it’s hard for me to understand why more people don’t embrace it. I’m impatient with people and teams who don’t move forward. “Fail fast-forward” is a favorite motto of mine. It’s about not being afraid to fail, and if you do, identify it quickly and move ahead fast so no momentum is lost. It’s very acceptable to try things that ultimately fail. Just get going again.

Besides, there will always be critics. When I took this job, some said I was too old to run Yahoo! or didn’t understand online media. If I had wasted time worrying about that, or any other time I was criticized for being good at math or a good leader or even for being a woman, where would I be?

I recently took some heat from the media over our agreement with Microsoft and search, but I know it’s a great move for the long-term success of Yahoo!. Making the decision and driving this much change for us was hard but it’s done.  So now we’re moving forward, attacking our future, which is incredibly bright.

Being an optimist is very powerful, and the most successful people I know share this trait. Henry Ford was right: Whether you think you can, or think you can’t, you are right.

I’ve never been interested in agonizing over what could have or should have happened. I’ve found it much more useful to look ahead, not be afraid to fail, make the tough decisions – and to just deal with it. As my grandmother always said.

Here’s Andy Serwer’s interview with Bartz at the Summit:

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