Skip to main content
The Incentives Lab
HBT-COG-0649 · Dimension COG · Cognition

Sunk Cost Fallacy

Throwing more in because we already threw a lot in.

Decision Bias·Cognitive Bias·Grade B·draft· enriching…

Scientific Definition

Throwing more in because we already threw a lot in.

Plain-English Definition

Throwing more in because we already threw a lot in.

Feynman Explanation

We've spent $20M; let's spend $5M more to feel better about the $20M.

Core Principle

Throwing more in because we already threw a lot in.

Mechanisms

Psychological

Throwing more in because we already threw a lot in.

Behavioral Economic

Pending editorial review.

Neurological

Pending editorial review.

Evolutionary

Pending editorial review.

Sociological

Pending editorial review.

Computational

Pending editorial review.

Systems

Pending editorial review.

Inputs (Triggers)

Pending editorial review.

Outputs (Behaviors)

Pending editorial review.

Behavioral Signature

We've spent $20M; let's spend $5M more to feel better about the $20M.

Examples

Everyday
  • Five-year initiative kept alive purely because killing it 'wastes' the spend.
Modern (Organizational)
  • Portfolios bloated with bets no one would start today.
Historical

Pending editorial review.

Famous Experiments

Pending editorial review.

Design Principles

  • Ask: 'If we were starting fresh, would we fund this?' Honor the answer.

Measurement Approaches

Pending editorial review.

Evidence

Evidence Grade
B (A strongest → E speculative)
Replication
★★★☆☆
Intervention Confidence
3 / 5
Consensus
Pending editorial review (HBT v1.0 auto-seed).
Limitations
Pending editorial review (HBT v1.0 auto-seed).
Open Research Questions

Pending editorial review.

Primary References

Pending editorial review.

Signature Section

The Perverse Incentive Lens™

How this behavior is exploited — and how to redesign around it.

Exploitation
Legacy systems preserved because of integration cost, not value delivered.
Amplifying Incentives
Portfolios bloated with bets no one would start today.
Org Failure Modes
Portfolios bloated with bets no one would start today.
Societal Failure Modes
Pending editorial review (HBT v1.0 auto-seed).
Ethical Considerations
Pending editorial review (HBT v1.0 auto-seed).
Redesign Strategies
Ask: 'If we were starting fresh, would we fund this?' Honor the answer.
Diagnostic Questions
  • Ask: 'If we were starting fresh, would we fund this?' Honor the answer.
Warning Signs

Pending editorial review.

Red Flags

Pending editorial review.

Intervention Playbook
Individual
Ask: 'If we were starting fresh, would we fund this?' Honor the answer.
Team
Pending editorial review (HBT v1.0 auto-seed).
Organization
Pending editorial review (HBT v1.0 auto-seed).
Policy
Pending editorial review (HBT v1.0 auto-seed).
AI Implications
Detection
Legacy systems preserved because of integration cost, not value delivered.
Measurement
Pending editorial review (HBT v1.0 auto-seed).
Mitigation
Pending editorial review (HBT v1.0 auto-seed).
Responsible Use
Pending editorial review (HBT v1.0 auto-seed).

Interactive Mini Network

Click any neighbor to re-center the graph and follow the threads of connection.

HBT-COG-0649 · COG
Sunk Cost Fallacy
SCABAction BiasAHAffect HeuristicABAnchoring BiasDEDecoy EffectDEDefault EffectEEEndowment EffectFEFraming EffectHDHyperbolic DiscountingIEIKEA EffectIBInformation Bias

Knowledge Graph Neighbors

Version History

v1.1.0 · 2026-06-28Initial auto-seed from corpus.