In WWII, researcher Abraham Wald was assigned the task of figuring out where to place more reinforcing armor on bombers. Since every extra pound meant reduced range and agility, optimizing these decisions was crucial. So he and his team looked at a ton of data from returning bombers, noting the bullet hole placement.

They came up with numerous diagrams that looked like this:

See the source image

Most of his team members observed “Wow! Look at all those bullet holes in the center of the fuselage and on the wing tips! The armor clearly ought to go there, because those are the areas that are most marked-up in red!”

But Wald realized that they were only looking at those bombers which SURVIVED, and he correctly argued that these areas were instead precisely the damage areas that were already most survivable, while the areas which were NOT marked by bulletholes meant they were fatal. In so doing, he helped us understand “survivorship bias” — that is, if we only sample from the successful outcomes, we avoid seeing the crucial factors that caused failure, which in many cases are the most important factors of all.

Such survivorship bias can lead to conclusions and strategies which are precisely the opposite of optimal, so pay attention to the datapoints that you may have already artificially and incorrectly eliminated. 


Steve's an entrepreneur and software leader. Most recently, he founded, a way to create celebration cards easily. He also founded, helping people discover and share productive ways they can respond in times of crisis. Steve's worked on consumer apps, online travel, games, relational databases, management consulting and telecom. He launched Alignvote in 2019, which helped Seattle voters find their best-match political candidates. Steve founded BigOven, the first recipe app for iPhone, now with more than 15 million downloads, which was purchased in 2018. Steve served as Chairman of Escapia Inc., the leading SaaS solution for the US vacation rental industry, sold to Homeaway, now part of Expedia. In 1997, Steve was cofounder, President, CEO and Chairman of VacationSpot, a pioneer in the online reservation of vacation rentals, bought by Expedia in January 2000. At Expedia, Steve was Vice President of Vacation Packages, leading the vacation package and destination services teams, helping to create two patents on the first-ever dynamic vacation packaging system on the Internet, which now represents billions in annual transactions for Expedia. He has keynoted on several occasions at the Vacation Rental Managers Association (VRMA), and taught a graduate level course on the strategic management of innovation at the University of Washington Foster Business School in Seattle, Washington. Steve worked for Microsoft from 1991 to 1997 in a variety of senior marketing and executive positions, and led the creation of the internet games group, helping develop several products and patents related to online multiplayer gaming. He helped launch Microsoft Access and was involved in the acquisition of Fox Software by Microsoft in 1993. He's worked for IBM, Booz-Allen Hamilton and Bell Communications Research. He holds an MS in Computer Science from Stanford University in Symbolic and Heuristic Computation (AI), an MBA from Harvard Business School, where he was named a George F. Baker Scholar (awarded to top 5% of graduating class), and a dual BS in Applied Mathematics / Computer Science and Industrial Management from Carnegie Mellon University (CMU) with University Honors. Steve volunteers when time allows with Habitat for Humanity, University District Food Bank, YMCA Seattle, Technology Access Foundation (TAF) and other organizations in Seattle.

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