An excellent essay from Tom DeMarco and Timothy Lister's marvelous book - Peopleware: Productive Projects and Teams.
For most thinking workers, making an occasional mistake is a natural and healthy part of their work. But there can be an almost Biblical association between error on the job and sin. This is an attitude we need to take specific pains to change.
Speaking to a group of software managers, we introduced a strategy for what we think of as iterative design. The idea is that some designs are intrinsically defect-prone; they ought to be rejected, not repaired. Such dead ends should be expected in the design activity. The lost effort of the dead end is a small price to pay for a clean, fresh start. To our surprise, many managers felt this would pose an impossible political problem for their own bosses: "How can we throw away a product that our company has paid to produce?" They seemed to believe that they'd be better off salvaging the defective version even though it might cost more in the long run.
Fostering an atmosphere that doesn't allow for error simply makes people defensive. They don't try to systematize the process, when you impose rigid methodologies so that staff members are not allowed to make any of the key strategic decisions lest they make them incorrectly. The average level of technology may be modestly improved by any steps you take to inhibit error. The team sociology, however, can suffer grieviously.
The opposite approach would be to encourage people to make some errors. You do this by asking your folks on occasion what dead-end roads they've been down, and by making sure they understand that "none" is not the best answer. When people blow it, they should be congratulated-that's part of what they're being paid for.