Agile acknowledges mistakes

The agile manifesto states:

• Individuals and interactions over processes and tools
• Working software over comprehensive documentation
• Customer collaboration over contract negotiation
• Responding to change over following a plan

I don't think this actually identifies the power of agile. I believe if pressed people would argue this is true of all the processes. I really don't think people are that dense.

One of the things agile does that other prcesses don't do is acknowledge mistakes. It has a process (iterations) for discovering and fixing mistakes.

In the first months of a project you need to teach your customer mistakes are OK. Count requirements mistakes, development mistakes, testing mistakes, all the mistakes you can think of. Show how they are dealt with and how it is not a big deal.