Module 1 "Bad Map"

I have used so many very poor maps but did not keep any of them. These were usually handouts at tourist spots that offered no information, no help and resulted in total confusion.
I found this example at http://www.xefer.com/2008/04/maps. This map is showing foreclosures in Chicago for two years. It is trying to communicate the change in foreclosures for these two consecutive years. The scale and the symbolism chosen doesn't relay to the audience the data that the map is trying to show. The labeling is the only useful information derived from the map.