An interesting story from the mid-90s, when US carmakers wanted to enter the Indian market. However, the prices of their cars were high for the Indian market. So, they asked the car designers which features from the car could be eliminated to make it affordable.
Designers made an assumption by looking at US customers and eliminated what they felt were unnecessary features for India, including power windows in the rear.
Indian consumers who could afford these cars mostly had chauffeurs to drive their cars. This ended up as an odd design and experience where chauffeurs had power windows while the owners sitting in the rear had to hand crank the rear windows.
While not all assumptions can be field-tested, having empathy and understanding of customers could greatly reduce these design blunders.
Thinking Space 