Effective Segmentation Often Begins with the Analysis of Macrolevel Bases

Effective segmentation often begins with the analysis of macrolevel bases of segmentation, and then continues with the identification of microsegments within each potential macrosegment using microlevel bases of segmentation. However, segmentation can effectively end after considering only macrolevel variables. Please provide an illustration of a situation where only macrolevel bases are used to identify market segments and what variables or issues business marketers should use to determine whether macrosegmentation alone is enough for effective organizational market segmentation.