Sebelius said she decided to stay in the post for Obama's second term, wanting to wait till the end of Healthcare.gov's open enrollment period.
"Well, actually, I made a decision at the election that I couldn't leave along with a lot of my colleagues who left at the end of the first term," she said. "I also thought that, at the end of open enrollment was a logical time to leave."
Sebelius said that Obama didn't try to make her stay, because "made it pretty clear that that really wasn't an option, to stay on."
Sebelius, who presided over the tumultuous launch of the online health care exchange, admitted that rollout was "was terribly flawed and terribly difficult." But she also touted Obamacare's recent sign-up success.
"We announced last week that seven and a half million people, most of them coming through the site had enrolled. We're running the sites of 34 states through one situation. The hub, which all states connect to, has worked flawlessly from the beginning," she said. "Could we have used more time and testing? You bet. I've said that from the start. But the site actually works. And the great thing is, there's a market behind the site that works even better."
Sebelius said that she can now see how the administration's original October 1 launch deadline was "flat out wrong," but said she was proud of what Obama care had accomplished.
"I think what we said from the outset was, you know, this was fixing a very broken market -- where individuals really were on their own," she said. "So, that was fixed."