By far the most common mistake is to treat a generic situation as if it were a series of unique events; that is, to be pragmatic when one lacks the generic understanding and principle. This inevitably leads to frustration and futility.

My eureka moment was this: better teams probably don't make more mistakes, but they are able to discuss mistakes

Good failures are those that bring us valuable new information that simply could not have been gained any other way.

Chapter Two: Eureka!

“Mistakes are deviations from known practices. Mistakes happen when knowledge about how to achieve a certain result already exists but isn’t used.

Making mistakes was not evidence of stupidity but rather of inexperience. Making mistakes was a necessary part of learning something new—especially something difficult.