Design Thinking

Origin. Rittel and Simon; codified at IDEO and the d.school.

Mechanism. A five-stage loop — empathize, define, ideate, prototype, test — with the load carried by the prototype step: it converts an argument about what users will do into an observation of what they did.

Procedure. Observe users without leading. Write a point-of-view statement naming user, need, and insight. Diverge. Build the cheapest artifact that can be wrong. Test with real users. Return to any prior stage.

Applies to. Problems where the specification is unknown and the users are reachable.

Limitations. Where users cannot articulate needs, cannot be observed, or are not the payer, the empathize stage returns noise and everything downstream inherits it.