Don Goldstein learned a classic lesson when he joined an insurance company in the mid-1990s as vice president of IT. He inherited a data warehouse project intended to mesh information across divisions to provide a complete look at each customer.

"This would be the thing that finally gave everyone what they had been looking for," Goldstein recalls. "Namely, how do we get all of our information to mean something?"

But too much data needed too much cleansing, he says, and the project plan allowed many months between deliverables. Along the way, business groups argued about who should update which information.

"It just got way, way out of hand," he says. "It cost too much, took too much time. It didn't have a hope to work."

A data warehouse was finished, but for just one business unit. Users still had to ask IT to generate their reports. The project died soon after being delivered to the business unit, when key project members left and funding dried up.

The lesson he learned, of course, is that you can't boil an ocean. Ever after, says Goldstein, who is now CIO of CB Richard Ellis, a $5 billion commercial real estate services company, his projects have had narrow and specific milestones managed by a group of IT and business people, each accountable for different aspects of the work.

"It seems simplistic, looking back," he says. But the failure so affected him that he avoids the term "data warehouse." "So ominous," he says. You can almost see him shiver.

How you respond to failure—or any event that doesn't go as expected—shapes how you handle the next one. Early in her career, Twila Day, CIO of the $37.5 billion Sysco food service company, had to find the skills and inner strength to handle a negative boss. She's since applied the lesson to deal with negative people generally. "You learn more when something goes wrong than when everything goes right," she says.

Surviving failure not only teaches lessons but builds resiliency—a trait critical to handling the uncertainty we face today. In this economy, which yet shows no signs of great and lasting recovery, you want tested leaders cool enough to handle difficult, unpredictable days. Someone who has never failed is half as valuable as someone who has endured a "humbling experience" and learned from it, says John Puckett, DuPont's CTO of corporate IT and CIO of central research and development. Puckett's 42-year career includes the CIO post at Toysmart.com (a casualty of the dotcom bust) as well as vice president and general manager at Polaroid (whose business model was overtaken by the rise of digital cameras). "You better hope your leaders have failures under their belts," he warns.