If you decide to study how to build bridges, you will start out with calculus, build a background in science of materials and then a guided tour of approaches to structure-building. In addition, you have to learn typical environmental factors. And, of course, there are workflow patterns and human factors involved in actually constructing a typical bridge. Oh, and sure, there will be a bit of CAD. Let's apply this met…
Meh. If you read The Design of Everyday Things and then look around, you see so many faults with the UI of physical things, even some which have been around for more than a century. A good example is packaging: "The Consumer Product Safety Commission estimated that attempts to open packaging caused about 6,500 emergency room visits in the U.S. in 2004."
E.g. clamshell/tamper-proof packaging is awful (I like calling it "customer-proof"), but the goal to reduce theft is a much higher priority than making it easier to open.