Survivorship Bias
Understanding Survivorship Bias
Survivorship Bias
We tend to focus on successes while ignoring failures, leading to distorted conclusions. This bias can make risky ventures seem safer than they actually are.
What is Survivorship Bias?
Survivorship bias is a mental shortcut where we focus on successful cases while ignoring the ones that failed. This can lead to overly optimistic conclusions because we don’t see the full picture. The failures—often just as instructive—remain hidden from view.
Why Does This Happen?
We naturally seek patterns in the information we have. But if that information is incomplete (only showing successes), our conclusions can be wildly inaccurate. This bias appears in business, investing, self-improvement advice, and even historical analysis.
Real-World Impact
- Business Myths: People assume copying successful startups will lead to success, ignoring thousands that failed with the same strategies.
- Investing Fallacies: We celebrate winning stocks but forget companies that disappeared from the market.
- Service Quality Surveys: A company surveys only customers who made a purchase about their experience. They conclude their service is excellent, but they fail to account for those who never bought anything—possibly due to poor service. This leads to an overly positive but misleading conclusion.
Understanding survivorship bias helps us make more informed, realistic decisions by considering both success and failure cases.

Visual representation of Survivorship Bias (click to enlarge)
Examples of Survivorship Bias
Here are some real-world examples that demonstrate how this bias affects our thinking:
Psychological Study Simulation
Experience a famous World War II study that revolutionized aircraft protection and revealed a crucial insight about data analysis. You'll examine damage patterns on bomber aircraft and discover how a counterintuitive solution saved many lives.
Customer Service Survey Bias
A company wants to measure customer satisfaction, so they send surveys to people who made a purchase. The results show overwhelmingly positive feedback, leading the company to believe their service is excellent. However, they failed to survey potential customers who never completed a purchase—possibly because of poor service. By only analyzing those who bought something, they miss critical data and make flawed conclusions about their overall service quality.
Startup Success Illusion
Entrepreneurs often read about the few startups that became billion-dollar companies, believing that following their strategies will lead to success. However, they rarely hear about the countless failed startups that followed the same paths but disappeared. Ignoring these failures creates an illusion that success is more common than it actually is.
The Myth of College Dropouts
We often hear stories of successful college dropouts like Steve Jobs and Mark Zuckerberg, leading many to believe dropping out increases the chance of success. However, this ignores the vast majority of dropouts who did not achieve similar success. The unseen failures distort our perception of reality.
How to Overcome Survivorship Bias
Here are strategies to help you recognize and overcome this bias:
Seek Out the Missing Data
Actively look for cases that didn’t succeed. Understanding why they failed provides a more realistic perspective on success rates.
Consider Base Rates
Use statistical data to understand the true likelihood of success, rather than focusing only on examples of those who made it.
Beware of Cherry-Picked Success Stories
When reading success stories, ask yourself: 'What happened to everyone else who tried the same thing?'
Test Your Understanding
Challenge yourself with these questions to see how well you understand this cognitive bias:
A consultancy firm is analyzing the effectiveness of a new marketing strategy. They focus on companies that successfully increased sales after implementing the strategy. What is the flaw in their approach?
Academic References
- Taleb, N. N. (2007). The Black Swan: The Impact of the Highly Improbable.
- Wald, A. (1943). A Method of Estimating Plane Vulnerability Based on Damage of Survivors.