Using FitNesse allows you to communicate with the customer up front. Before a line of code is written, you can have all the behavior expressed in an executable format.
You find your self delivering software to your customer who says “That’s not what I asked for.”
Make sure the customer helps to write these tests. Once your FitNesse test is in place, all you need to do it make it pass. Due to the cut-and-dry aspect of executable specifications (FitNesse test), once the spec is passing, you have delivered precisely what your customer asked for.
Bugs sneak into your system as development progresses and these bugs takes weeks to find and remove.
FitNesse is a tools to help you drive development with tests. When practices with discipline, test driven development will insure that you have a FitNesse test for each and every feature in your system. The moment a bug is introduced, you will know about it because a FitNesse test will fail.
It is difficult to create documentation for your system and it is constantly out of date because the system is changing.
FitNesse offers a unique documentation solution. When ever you write a FitNesse test, you are in fact describing how the system works. In other words you’re documenting it. The web/wiki based nature of FitNesse makes documentation simple and convenient.
The best part is that the documentation in FitNesse can never go out of date. Since you’re keeping your test passing, and your tests are documentation, it’s impossible for them to lie.
There is an article I wrote about FitNesse for Windows Developer Power Tools. This book, just released today, includes articles on dozens of free tools that .NET developers might benefit from.
If you write .NET code, check it out. If not, keep in mind that FitNesse will work for almost any language.