---

name: prototyping-concept-throwaway-evolutionary description: 'Use this skill when picking which kind of prototype to build for the question at hand — concept (exploratory), throwaway (testing one specific aspect), or evolutionary (incremental toward final). Trigger when planning a research method, when scoping a technical spike, or when deciding whether an MVP should evolve or be thrown away. Sub-aspect of prototyping; read that first.'

The three prototype kinds

The book identifies three prototype kinds — concept, throwaway, evolutionary — each with characteristic uses, costs, and failure modes.

Concept prototypes

For exploring preliminary ideas. Quick, cheap, often disposable.

Use for: brainstorming sessions, early stakeholder alignment, exploring whether a direction is worth pursuing.

Examples: paper sketches, storyboards, mood boards, foam mockups, role-playing.

Failure mode: artificial reality problem. A skilled designer can make any concept look plausible; the prototype's polish doesn't predict actual workability.

Throwaway prototypes

For testing specific aspects of a design.

Use for: performance benchmarks, A/B tests, single-flow user studies, technical spikes.

Examples: standalone interactive demos, wind-tunnel models, isolated code experiments.

Failure mode: scaling and integration problem. A throwaway that works in isolation may fail when integrated or at scale.

Evolutionary prototypes

For incrementally building toward the final design.

Use for: MVPs that grow into products, iterative startup development, products with uncertain requirements.

Examples: software MVPs, agile sprint outputs, lean startup builds.

Failure mode: tunnel vision. Iterations refine the current direction; teams may miss fundamentally better directions.

Picking the right kind

Situation	Prototype kind
Exploring ideas; "is this worth doing?"	Concept
Testing one specific question	Throwaway
Iterating toward a final product	Evolutionary
Stakeholder alignment	Concept
Performance benchmark	Throwaway
Scaling a startup	Evolutionary

The kinds aren't mutually exclusive. A typical project uses concept prototypes early (to align), throwaway prototypes mid (to test specifics), and evolutionary prototypes late (to ship and refine).

Combining the kinds

A common pattern:

1. Concept prototypes to explore directions and align stakeholders.
2. Throwaway prototypes to test specific risks (performance, user flow, integration).
3. Evolutionary prototyping to build the actual product, informed by what concept and throwaway prototypes revealed.

Each kind catches different issues; using all three reduces the risk of any single failure mode.

Resources

• Lidwell, Holden, Butler — Universal Principles of Design (2003).
• Schrage, M. Serious Play (1999).
• Brooks, F. The Mythical Man-Month (1995).
• Boehm, B. "A Spiral Model of Software Development and Enhancement" (1986).