How much extra costs of the project can often be attributed to a lack of quality?

The Cost of Poor Quality separated these costs into 3 categories:

• Prevention Costs: Including quality planning, training, preventive maintenance, housekeeping etc.
• Appraisal Costs: Including testing, inspection, audits, reviews and surveys, etc.
• Failure Costs:
  • Internal Failures: Including scrap, rework, expediting, equipment downtime, injuries, etc.
  • External Failures: Including product recalls, returned products, complaint handling, lost sales, etc.