Defect definition

A defect, in quality terms, is a failure to meet specifications or a reasonable expectation for use. There are four classes of defects:

1. Very serious: could lead to severe injury or catastrophic economic loss
2. Serious: could result in significant injury or economic loss
3. Major: could result in major problems with intended or reasonably foreseeable use
4. Minor: could result in minor problems with intended or reasonably foreseeable use

Defects are waste, so to lower costs reduce or eliminate defects. Don't forget to take customer expectations into consideration when identifying defects.