What do customers really want?

http://resultsbrief.bain.com/videos/0903/index.htm
Most preference-rating tools are flawed because customers have a hard time articulating their true desires. To remedy that problem, companies need a way to help their customers sharpen the distinction between what's "nice to have" and what they "gotta have."  Maximum Difference Scaling (or "Max Diff") ratings ask customers to make explicit trade-offs, allowing their real preferences to emerge.