When evaluating whether test first or test driven development is worthwhile I would encourage a holistic approach. What is the total cost to the organization for the development, quality assurance, deployment and maintenance of the software? On its first release? Over its lifetime?<p>Carefully consider the alternatives. No testing? Manual testing? Automated UI testing? Test second?<p>On the softer side (and more difficult to measure) I ask development teams how test first affects their thinking. Do you converge on users' requirements more quickly or slowly?<p>Finally, recognize that programming is a hard skill to master. TDD is another skill on top of that one.