1. Manpower
   1. Insufficient training and skills of employees can lead to improper assembly or improper handling of components.
   2. Lack of experience or knowledge in operating machinery can result in errors during the manufacturing process.
   3. Fatigue or physical limitations of the workforce may lead to decreased focus and attention to detail.
2. Methods
   1. Inadequate or outdated manufacturing processes may introduce inefficiencies or inconsistencies in production.
   2. Inefficient or ineffective quality control procedures can cause defects to go unnoticed.
   3. Lack of standardized work instructions may result in variations in the manufacturing process.
3. Machines
   1. Equipment malfunction or breakdown can contribute to defects in the final product.
   2. Inaccurate or imprecise measurement instruments may lead to inaccurate product specifications.
   3. Poor maintenance and inadequate calibration can result in deviations from desired production conditions.
4. Materials
   1. Inferior quality raw materials or components can negatively impact the final product's quality.
   2. Variability in material properties may contribute to inconsistencies or defects.
   3. Insufficient material inspection or testing can allow defective materials to enter the production process.
5. Measurements
   1. Faulty or unreliable measurement methods can result in inaccurate data.
   2. Inaccurate or imprecise measuring instruments may lead to incorrect measurements.
   3. Inadequate data collection and analysis hinder the identification of potential issues or patterns.