The entrepreneur who persists with a failing strategy longer than the evidence warrants is not being irrational in any simple sense. They are being precisely rational within the psychological framework that the sunk cost mechanism installs: a framework where continued commitment creates the possibility of vindication and exit permanently forecloses it. Understanding the mechanism changes what can be done about it.

The foundational finding and why personal responsibility is the amplifier

Staw’s (1976) Knee-Deep in the Big Muddy experiment established the foundational mechanism. Participants who had made an investment decision and had personal responsibility for it committed significantly more resources to a failing course than those who had inherited the same decision from someone else — despite being presented with identical evidence that the course was not working. The driver was not ignorance of the evidence. It was self-justification: abandoning the course required acknowledging that the prior decision was wrong, which threatened the self-concept of the person who made it.

The personal responsibility finding has a direct entrepreneurial application. The founder who made every significant strategic decision in the company’s history has maximum personal responsibility for every investment. They cannot distribute the self-justification motive across a committee or a management team. When exit becomes warranted, it is a personal admission at full force — which is precisely why the founder is the person most vulnerable to sunk cost escalation and least able to perceive it in themselves.

Arkes and Blumer’s (1985) formalisation confirmed the irrationality the mechanism produces: what has already been spent is unrecoverable regardless of future action. The continued investment cannot retrieve it. But the psychological weight of prior expenditure consistently drives decisions as though it could — as though enough additional commitment might eventually convert the sunk cost into a justified investment.

How identity fusion makes the entrepreneur’s sunk cost problem categorically worse

The standard sunk cost experiment involves participants whose self-concept is not fused with the course they have invested in. The entrepreneurial context is categorically different. Pierce, Kostova and Dirks’s (2003) psychological ownership research and Cardon et al.’s (2009) identity centrality findings together establish that for passionate entrepreneurs, the business is a self-extension. Every strategic decision, creative contribution, and relational commitment made through the business is identity-invested.

The failing course is not merely a failed strategy. It is a failed self-extension. Exit requires not just acknowledging wasted financial and temporal resources but accepting that the identity that was invested in those decisions was inadequate. The escalation of commitment in this context is substantially more severe than the standard experimental findings predict — because the stakes are not merely commercial. They are existential in the sense that Linville’s self-complexity research predicts: the entrepreneur whose identity lives primarily in the business has no stable ground to stand on when that business requires them to admit it is failing.

Why the clearest evidence produces the strongest commitment

Ross and Staw’s (1993) escalation research documented a pattern that is counter-intuitive until the mechanism is understood. When project failure evidence became unambiguous — when it could no longer be explained away through external attribution or optimistic reframing — the escalating decision-maker sometimes increased rather than decreased commitment. The mechanism is self-protective rationalisation: at the point where the evidence is too clear to ignore, increased commitment becomes a social signal of confidence in the project’s viability. The observable behaviour — continuing to invest — becomes a statement about belief, made to investors, employees, and the entrepreneur themselves. Exit at this point would not merely acknowledge the failure; it would implicitly acknowledge that the increased commitment was itself a mistake.

This is the kill signal paradox: the moment of clearest evidence is also the moment of greatest psychological resistance, because the self-justification motive and the social signalling motive are both operating at maximum intensity simultaneously.

How prospect theory explains why exit feels worse than it is

Kahneman and Tversky’s (1979) prospect theory predicts the specific reference point mechanism. The entrepreneur evaluates the failing course against the reference point of prior investment — not against the neutral baseline. This means losses below the sunk cost reference point are experienced as losses relative to an already-invested amount, weighted approximately twice as heavily as equivalent gains. Exit from a failing position feels disproportionately painful not because the absolute financial reality warrants that pain, but because the prospect theory reference point is the sunk cost itself.

The asymmetric loss weighting produces the characteristic entrepreneurial sunk cost experience: the objective case for exit is clear, but it feels worse than staying — not because staying is better but because the psychological pain of exit is amplified by the reference point that prior investment has established.

What pre-commitment actually prevents

DeTienne’s (2010) research on entrepreneurial exit established that planned, anticipated exit — building explicit exit criteria into the venture from the beginning — is the most reliable preventive mechanism for sunk cost escalation. The entrepreneur who has pre-committed that a specific metric not achieved by a specific date will trigger a defined response cannot use the self-justification rationalisation at that moment. The exit is not a personal failure in the same psychological sense. It is the execution of a plan — made when the sunk cost psychology was not yet operating, when the outside view was available, and when the pre-commitment was not threatening to an identity that had not yet been invested in the position.

The pre-mortem provides the related debiasing mechanism for decisions already in progress. By explicitly imagining the project as already having failed before committing to continued investment, the entrepreneur activates the loss-framing and outside-view perspective that sunk cost avoidance suppresses. Prospective hindsight — the cognitive shift produced by treating the future failure as an already-occurred event — generates more accurate causal reasoning than forward projection, allowing the entrepreneur to perceive the failure signals that the commitment-preserving mindset is actively filtering out.

Books worth reading on this

The Dip by Seth Godin. Godin’s account of the strategic difference between the temporary setbacks that precede genuine success and the dead ends that warrant abandonment is the most practically focused available treatment of the sunk cost problem from the perspective of knowing which commitments to honour and which to exit. His specific account of the psychological conditions that make the dip and the dead end feel identical from inside them is directly relevant to the kill signal paradox that Ross and Staw’s research documents. Misbehaving by Richard Thaler. Thaler’s account of the behavioural economics research programme — including his own work on mental accounting, loss aversion, and the endowment effect — provides the most readable available treatment of the full family of psychological mechanisms through which prior investment distorts future decisions. His specific account of how the mental accounting of sunk costs operates across contexts — including the entrepreneurial ones — is the most accessible treatment of the prospect theory mechanism this article is built on.

If the dynamics described here are significantly affecting your wellbeing, speaking with a psychologist is the right next step. UK: Samaritans (116 123, free, 24/7). Mind (0300 123 3393). BACP: bacp.co.uk/search/Therapists. Crisis Text Line — text HOME to 741741 (US, UK, Canada, Ireland). International: internationaltherapistdirectory.com.

This article is for educational and informational purposes only. Sources: Staw, B.M. (1976), Knee-Deep in the Big Muddy: A Study of Escalating Commitment to a Chosen Course of Action, Organizational Behavior and Human Performance, 16(1), 27–44. Arkes, H.R. & Blumer, C. (1985), The Psychology of Sunk Cost, Organizational Behavior and Human Decision Processes, 35(1), 124–140. Pierce, J.L., Kostova, T. & Dirks, K.T. (2003), The State of Psychological Ownership, Review of General Psychology, 7(1), 84–107. Cardon, M.S. et al. (2009), The Nature and Experience of Entrepreneurial Passion, Academy of Management Review, 34(3), 511–532. Kahneman, D. & Tversky, A. (1979), Prospect Theory: An Analysis of Decision under Risk, Econometrica, 47(2), 263–291. Ross, J. & Staw, B.M. (1993), Organisational Escalation and Exit: Lessons from the Shoreham Nuclear Power Plant, Academy of Management Journal, 36(4), 701–732. DeTienne, D.R. (2010), Entrepreneurial Exit as a Critical Component of the Entrepreneurial Process, Journal of Business Venturing, 25(2), 203–215. Klein, G. (2007), Performing a Project Premortem, Harvard Business Review, 85(9), 18–19. Duke, A. (2022), Quit: The Power of Knowing When to Walk Away, Portfolio. Godin, S. (2007), The Dip, Portfolio. Thaler, R.H. (2015), Misbehaving: The Making of Behavioural Economics, W.W. Norton.