[OneTimePetes]

Its the symbolism- returning to a earlier stage of planing. Take building a house- the moment you have to redraw the plans, the previous work is usually a tear-down.

Often enough - that is the case in the real world. Berlin Airport, was a waterfall project, were several times additions were added, late in production.

Now that image carries only halfway into the software world, as alot of the other abstractions (classes, modules, interfaces) will survive, even a replanning and rewrite in waterfall.