Rumsfeld was describing a world characterized by uncertainty, insecurity and ambiguity. And he actually made a valid point about how leaders face situations where complete knowledge is not, and cannot, be available.

This awareness of a lack of knowledge is something we call a state of "unknowingness." And our research suggests, perhaps surprisingly, that it can be a good thing for leaders and the organizations they run.

Assuming that leaders—whether that's a prime minister, football manager or head teacher—should be heroically omniscient is not good for anyone. It places impossible expectations on people who cannot be masters of every context or complexity, and it disempowers others in the organization. How can they come up with solutions if they think their leader has (or should have) all the answers?

We also found that if "unknowingness" is recognized and accepted, it can lead to better decision making across an organization—and improved leadership overall.

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