What is the importance of QA documentation? - Software Quality Testing

What is the importance of QA documentation?

-Every QA practice should be documented.

-Designs, business rules, specifications, configurations, code changes, inspection reports etc. need to be documented.

-The progress of the software product can be measured by documenting QA.

-Change management documentation helps isolating development team resources for better productivity.

-The overall productivity of every software product can best be judged using QA documentation.