What is Defect Rate?
Defect Rate
The proportion of defects among products made.
What it means
Defective rate is the quantity defective divided by the quantity made. If you make 100 pens and 8 pens are defective, it is 8%.
The flow accumulated each day is more important than the daily numbers. If it suddenly rises, something has changed in the materials, equipment, or work methods.
At the pen factory
On the 12th day, 8 pens out of 100 black ballpoint pens were defective, resulting in a defect rate of 8%. On the 13th day, 3 pens out of 100 blue ballpoint pens were defective, or 3%.
Why it matters
Only by writing down the defects in numbers can you tell whether they have decreased or increased, and decide where to fix them.