Week 4 - Test-Driven Development lets you eliminate bugs as you code

http://techrepublic.com.com/5100-22-5077388.html

The site has briefly descript what is Test-Driven Development (TDD) and how can it be conducted. The cycle of the TDD is as mentioned in the site, I would like to pick some as a reference for this article:
1. Add a little test
2. Run all tests and fall
3. Make a little change
4. Run the test and success.
5. Re-Factor to remove the duplicate codes

It also shows some of the example on how to use the Debugger software to test the program automatically.

Test-driven development does good job especially for the small to medium-size of software development. What if such methodology apply to the large software development, say the Operating System for Super-computer? Certainly not!
On the other hand, there is a stage mentioned that the development of the software may stop in one phase if the programmer like to modify the code until it run prefect. Every software has bugs. We can never debug it and make it prefect. What would be the consequences of the programmer continue to test-code-run again and again? The product could certainly delay release.

In order to improve the TDD methodology, I think programmer need to set the due date of the release of the Alpha, Beta and Final release version in order to complete the task on time.