One thing I always wanted to hear from my development, quality, design and project management teams was that they made mistakes. As long as they were new mistakes I considered them great learning opportunities.
Every now and then I would see a repeat of something we had done wrong before. Pretty much always the reason the error would repeat was due to a failure to truly internalize the first experience into the (dare I say) processes in the organization.
Building an environment where individuals are not punished for making mistakes, especially new and more innovative mistakes is critical. They should be highlighted as successes!