I agree with @aaq2 and @myton‘s opinions. I would like to summarize a few main points and add a few more points to the ideas for improving quality control:
1. Define processses, streamline processes as @aaq2 has mentioned: By doing so, you can always check if there’s room for improvement. For ex: are there any steps that are uncessary, or any steps that are nescessary but skipped.
2. Qualiied candidates
3. Plan epeatable processes
4. Have a back-up/preventative plan
5. Good Communication plan
6. Lastly, plan for continuous improvement