Leading Practices:
Use the matrix to cluster ideas, not make decisions: The goal is to map ideas generated from ideation to guide a first pass at down selection.
Look for themes and clusters: This is where overlapping ideas or linkages between ideas can be seen. Some of the best solutions come from combining ideas.
Vary the axis: There is no right or wrong for what goes on the X or Y axis. Based on the situation – try a few and see how that changes how the ideas map out.