Jean-Paul S. Boodhoo

what you are saying is that NOT using TDD is "Technical Debt",  a term coined by Ward Cunningham.  

www.martinfowler.com/.../TechnicalDebt.html

I personally have not used TDD very much, but i would suspect that for small, simple projects, TDD is overkill because there is very little technical debt to be accrued, especially if you have strong developers.

@Fregas

Even if TDD is overkill in the "Technical Debt" department for small, simple projects, you still take away other valuable things from using TDD.

I liked this comparison :-), and to add some similarities: When you want to buy something, and want to pay with cash, you have to save up over some time - i.e. it's going to take a bit longer until you get the goods - whereas if you borrow you will get the goods sooner;  With TDD the initial release will be a bit later than if you just coded and delivered - but when you deliver it feels sooo much better!

@Matt Hornsby:

Like what?

@Fregas

I guess it depends on your definition of small/simple, but I think I know what you mean.

Personally, I find that a lot of small/simple projects end up growing/expanding, and that is when the TDD comes in handy.  I can make these enhancements with less pain.

As @Fregas said, small projects often grow (or get re-used), and this a often where simple, purpose-built components get misused and abused.  

Using TDD even on the simple items provides a solid set of regression tests to help prevent this "parasitic" growth from breaking the original logic.

Also, I find that creating exception cases where good programming practices can be skipped causes more harm than good down the road, like when some developer decides to move that line between "simple" and "not simple"

Remember, their is a difference between TDD and having a lot of tests.

TDD might be overkill ( or not your preference), but tests are a good thing no matter how small your project is.

The purpose behind TDD is not to develop regression tests, though this is a nice side effect.  The purpose of TDD is to provide a disciplined approach to writing the code.

TDD forces you to write code in very small increments.  It forces you to think carefully about the small piece of functionality that you are about to write.  I find that it is quite rare that my initial code fails the test (I'm not counting the pre-code run of the test).  This means I am getting the code written correctly the first time and avoiding debugging sessions and interminable integration or final test sessions.

TDD is not about testing - it is about writing the code correctly.