Manpower, Machines, Measurements, Materials, Methods, and Mother Nature
Source
Variation in processes can stem from any of the six “M”s:
Image from: https://sixsigmastudyguide.com/six-ms-6ms-or-5ms-and-one-p-5m1p/
These are the sources of variation in all processes (manufacturing and anything else).
Examples:
Manpower
- if workers are untrained, or have inherent differences in their capabilities or preferences
Machine
- Machines may degrade over time, and have imperfect tolerances even at their best
- Different machines might run the same applications differently
Mother Nature
- Weather affecting travel conditions
- Acts of God ruining materials in work (e.g. the roof caves in due to snow)
Measurements
- Metrics chosen do not correlate to process success
- Measurement errors due to units or inherent uncertainty
Method
- Variations in approach (e.g. waterfall vs agile, or drill press vs hand drill)
Materials
- this load of bread went moldy before that one did, despite them having the same due date
Source
6M’s in Six Sigma (Six Ms or 5Ms and one P or 5M1P)