Problems breed problems, and the lack of a disciplined method of openly attacking them breeds more problems.
The great discoveries are usually obvious.
It is always cheaper to do the job right the first time.
In a true zero-defects approach, there are no unimportant items.
Quality is the result of a carefully constructed cultural environment. It has to be the fabric of the organization, not part of the fabric.
If you don't know what the defect level is, how do you know when to get mad?