No thematic map is perfect. Some pixels or polygons are not accurately classified, no matter how well the map is crafted. Therefore, thematic maps need metadata that sufficiently characterize the nature and degree of these imperfections. To decision-makers, an accuracy assessment helps judge the risks of using imperfect geospatial data. To analysts, an accuracy assessment helps describe the reliability of the map for geospatial analyses and modeling, and the distribution of different types of "true" land cover within each mapped category. To producers of thematic maps, an accuracy assessment measures the degree of technical success for alternative algorithms or techniques. To project managers, an accuracy assessment helps determine contract compliance or measure performance of technical staff.
Czaplewski, Raymond L. 2003. Accuracy assessment of maps of forest condition: Statistical design and methodological considerations Chapter 5 . In: Wulder, Michael A.; Franklin, Steven E., eds. Remote Sensing of Forest Environments: Concepts and Case Studies. Boston, MA: Kluwer Academic Publishers. p. 115-140.