must support sales of both sofas and cars > Problem with current solution > While Sofas and cars have similar properties, a car isn't a logical extension of a sofa. > Scenario > The business has decided to sell cars in addition to sofas as they share similar characteristics (number of seats and color)
if sofa "is a car" > Problem with current solution > Language in code base does not match natural/business language > Scenario > Wheels are being added to sofas. Object + wheels = car in "fictional language".
sofa "is a car”. > Cars can be moved. > Problem with current solution > Requirement doesn't make sense. > Confirm actual requirement with person making them! > Scenario > Sofa location must be updated when moved. Person making requirements considers movable objects to be cars.