Its a subplan of the project managemente plan
Strategies for monitoring should be included in the plan as the reason for all the steps you are taking.
The team must understands the rationale behind the metrics being used to judge succes or fairlure of the project
2 Quality Checklists
To help people head off mistakes that might cause defects. Checklists can also be used for inspecting products to be sure that they display specific characteristics.
3 Quality metrics
Are the kinds of measurements you´ll take throughout your project to figure out its quality.
You need to write down the formulas you´ll use, when you will do the measurements, why you are taking them, and how you will interpret them.
4 Project document updates
might need to be made because you have found new information in the course of planning your quality activities that affects one of the other plans you've already made.
5 Process Improvement Plan
is a plan for improving the process you are using to do work. You set goals for how you can monitor the process during your project, and make recommendations to make it better.
It is another subplan of the project management plan.