Trust, but Verify

Trust among team members is good—usually. But with some teams, too much trust can actually depress performance, finds Claus Langfred, a professor of organizational behavior at Washington University in St. Louis.
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Failing to keep an eye on team members’ activities can be naive, Langfred concludes, regardless of levels of trust. So managers may want to require a modicum of oversight rather than let a team decide for itself. A little skepticism never hurt anyone—or any team.

("Trust, but Verify", by Gardiner Morse, Harvard Business Review, May 2005)