This Technique is Referred as 4M Technique
ANUJ KUMAR SHRIVASTAVA, Manager, India
the Fishbone is also referred to as the 4M model.
The 4 M's are as follows:
The origin is as not known very clearly but its appearance is understandable because when you're looking at a production system you usually find mistakes broadly in the above 4 categories, even if you proceed in detail you may find other causes. But you will notice also they tend to fall in either of the 4 categories. So we consider them as a base.
But with times people have modified it according to their convenience.