Washtenaw Dairy in Ann Arbor, Michigan, sells 63 flavors of Strohs Mooney's ice cream, and Ben and Jerry's Web site also lists 63 different flavors of ice cream. These numbers are similar to the varieties of cell phones sold by Samsung, Nokia, and Motorola. Toyota makes only 16 varieties of vehicles and Boeing makes 16 varieties of airplanes. Why is there more variety in cell phones and ice cream than in automobiles and airplanes?