It no longer becomes possible to define completely the details of a project when you are pushing the technology envelope. With the Mercury space project, the leap was aggressive with massive public attention. The planners who arranged that successful effort, formalized the iterative approach to new product development. They found it necessary to move beyond trying to define the desired result at the beginning and progressing in “waterfall” fashion to completion. Using the iterative method that they formalized, the Mercury project was organized into a series of experimental steps. The results of each step’s planned test provided the information needed to progress further. Obviously some of the tests ended in failure as we have seen in the news. The latest SpaceX, Blue Orion, Challenger disasters that literally explode into the public consciousness come to mind. Neil Armstong was asked to indicate what he thought was the dangerous part of space flight. He indicated it was the time between entering and leaving the space capsule
The Chrysler Minivan actually has the same cargo capacity as was offered in the smallest full size van at the time. Achieving this feat is a good example of iteration in action. One of my car designers described the task as stuffing 10 lbs into a 5 lb box. We did not wish to give up the ability to stow a full size spare. Since changing a flat is such a pain in the butt, it is unlikely that a traveler with a flat in the wilds of Laos will appreciate our efforts until he is writing his memoirs.
The basic challenge is that a full size tire did not fit between the rear axle and the rear bumper. Tough development tasks require superb executive planning. The advanced design team got the first kick at the can. They picked adding a kink into the axle. Fortunately planning a hand off to a second design team solves the issue of becoming attached to a mediocre solution simply because of pride in authorship. Offsetting the axle both down and forward proved to be the elegant solution. Having an overlap between the production design team and advance design team efforts mitigated the time lost by changing concept midstream. (We also got lucky because the kinked axel was the item that failed when the advance design was tested)
Iterative product development (in manufacturing we call this Kaizen) has emerged as the dominant strategy for launching software products. Following the tenants of lean startup, we launched http://mileagetrakker.com. A/B testing was used to tune our product so that the UX (user experience) is positive. Subsequent improvements are evaluated using the SCRUM approach where potential improvements are exposed to subsets of the user base. The first improvements that we implemented made more of an impact because diminishing returns sets in.