Russ had told him that back in the previous century, manufacturers had actually had to build physical prototypes to test their designs. Andy found it hard to imagine building something before you knew whether it would work or not. Physical manufacturing was a lot more costly than computer time, making such a venture a big investment gamble. Even if the design was mostly good, any unanticipated flaw could result in expensive retooling before production could start. Manufacturers were a lot smarter these days; they’d learned that it was a waste of good money to build something just to see if it worked.