Decision making comes in every stage of design. Consider two cars of different makes. They may both be reasonable cars and serve the same purpose but the designs are different. The designers consider different factors and come to certain conclusions leading to an optimum design. Market survey gives an indication of . | Fundamentals of Machine Design Module 1 Fundamentals of machine design Version 2 ME IIT Kharagpur Lesson 1 Design philosophy Version 2 ME IIT .