Logical Fallacies
Sunk Cost Fallacy
Continuing a failing project because of resources already invested.
What it is
Before & after
“We've invested two years in this platform, so we must continue despite better alternatives emerging.”
“The two years invested taught us valuable lessons. Based on current data, pivoting now will save resources and achieve better outcomes.”
When you’ll use it
Project management: 'We've already spent $2M, we can't stop now' despite clear failure indicators
Feature development: 'We've worked on this for 6 months' when user research shows no demand
Strategic initiatives: 'We've committed to this publicly' when market conditions have changed
Pro tip
Ask: 'If we were starting fresh today, would we choose this path?' Ignore past costs.
Questions & answers
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