To build a folly is essentially to do something a second time, something at an inopportune moment. That something is always the memory of something forgotten, about which we can paradoxically say "There it is again."
Follies were misunderstood, purposeless constructions. They were often only small, extravagant gestures in a garden, easily whisking off the imagination to distant lands, a sort of time capsule built to awaken the memory and induce surprise in passers-by. They marked locations, organized secondary paths in a park, or simply predicted the arrival of better times—a demarcation, a sacred spot, a mysterious trail, a hill whose tragic rocky nature begged for a tower, a party, or the arrival of summer.
“It is demonstrably true that things cannot be other than as they are. For, everything having been made for a purpose, everything is necessarily for the best purpose.” — Professor Pangloss
The Nintendo way of adapting technology is not to look for the state of the art but to utilize mature technology that can be mass-produced cheaply.
This is the reason a Nintendo console never has the fastest chips or the beefiest specs of its generation; instead, its remixes components in an interesting and generative way. Think of the Gameboy’s monochrome screen, the Wii’s motion controller, the Switch’s smartphone form.
[Gunpei Yokoi] is talking about reliability and predictability, in performance and supply alike. He wants the components to be boring, so their application can be daring.