A decision matrix consists of criteria, weightings, and scores for the purpose of making a decision.
At least that is what it appears to be on the surface.
We have all had the experience of creating a decision matrix, finding the winning decision, and then going back and changing the scoring or weightings so that a different decision comes out.
That is because a decision matrix is not for making a decision. A decision matrix is for us to look at the whole problem or domain. A decision matrix forces us to build awareness and understanding.
Once we have that understanding our brains automatically make the decision.
A map is not for making a decision on where to go, it is to understand the lay of the land so that you end up somewhere worthwhile.