The book answer is to perform a quality audit. This allows your quality management team to determine what errors in the manufacturing process are taking place, so they can be corrected. In real life it would also be important to meet with the customer to make sure that you have all of their requirements correctly identified.
What would you do in this situation?
A deliverable continues to have defects that have a possibility of ending your project
e) Perform a quality audit
f) Meet with customer
g) Build a scatter diagram
h) Build an affinity diagram
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