If you read Kent Beck's book Test-Driven-Development By Example you will find that a major theme is this idea of developer fear or reticence. From the Amazon b

If you read Kent Beck's book Test-Driven-Development By Example you will find that a major theme is this idea of developer fear or reticence. From the Amazon book description: Quite simply, test-driven development is meant to eliminate fear in application development. While some fear is healthy (often viewed as a conscience that tells programmers to "be careful!"), the author believes that byproducts of fear include tentative, grumpy, and uncommunicative programmers who are unable to absorb constructive criticism.