293 lines
6.6 KiB
Markdown
293 lines
6.6 KiB
Markdown
# Premortem Principles
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## The Psychology of Overconfidence
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### Why We're Systematically Overconfident
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**The Planning Fallacy:**
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- We focus on best-case scenarios
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- We ignore historical delays and failures
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- We assume "our case is different"
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- We underestimate Murphy's Law
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**Research:**
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- 90% of projects run over budget
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- 70% of projects run late
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- Yet 80% of project managers predict on-time completion
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**The fix:** Premortem forces you to imagine failure has already happened.
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---
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## Hindsight Bias
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### The "I Knew It All Along" Effect
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**What it is:**
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After an outcome occurs, we believe we "always knew" it would happen.
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**Example:**
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- Before 2008 crash: "Housing is safe"
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- After 2008 crash: "The signs were obvious"
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**Problem for forecasting:**
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If we think outcomes were predictable in hindsight, we'll be overconfident going forward.
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**The premortem fix:**
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By forcing yourself into "hindsight mode" BEFORE the outcome, you:
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1. Generate the warning signs you would have seen
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2. Realize how many ways things could go wrong
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3. Reduce overconfidence
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---
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## The Power of Inversion
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### Solving Problems Backward
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**Charlie Munger:**
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> "Invert, always invert. Many hard problems are best solved backward."
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**In forecasting:**
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- Hard: "Will this succeed?" (requires imagining all paths to success)
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- Easier: "It failed - why?" (failure modes are more concrete)
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**Why this works:**
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- Failure modes are finite and enumerable
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- Success paths are infinite and vague
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- Humans are better at imagining concrete negatives than abstract positives
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---
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## Research on Premortem Effectiveness
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### Gary Klein's Studies
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**Original research:**
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- Teams that did premortems identified 30% more risks
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- Risks identified were more specific and actionable
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- Teams adjusted plans proactively
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**Key finding:**
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> "Prospective hindsight" (imagining an event has happened) improves recall by 30%
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---
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### Kahneman's Endorsement
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**Daniel Kahneman:**
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> "The premortem is the single best debiasing technique I know."
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**Why it works:**
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1. **Legitimizes doubt** - In group settings, dissent is hard. Premortem makes it safe.
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2. **Concrete > Abstract** - "Identify risks" is vague. "Explain the failure" is concrete.
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3. **Defeats groupthink** - Forces even optimists to imagine failure.
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---
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## Outcome Bias
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### Judging Decisions by Results, Not Process
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**What it is:**
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We judge the quality of a decision based on its outcome, not the process.
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**Example:**
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- Drunk driver gets home safely → "It was fine"
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- Sober driver has accident → "Bad decision to drive"
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**Reality:**
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Quality of decision ≠ Quality of outcome (because of randomness)
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**For forecasting:**
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A 90% prediction that fails doesn't mean the forecast was bad (10% events happen 10% of the time).
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**The premortem fix:**
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By imagining failure BEFORE it happens, you evaluate the decision process independent of outcome.
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---
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## When Premortems Work Best
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### High-Confidence Predictions
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**Use when:**
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- Your probability is >80% or <20%
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- You feel very certain
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- Confidence intervals are narrow
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**Why:**
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These are the predictions most likely to be overconfident.
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---
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### Team Forecasting
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**Use when:**
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- Multiple people are making predictions
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- Groupthink is a risk
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- Dissent is being suppressed
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**Why:**
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Premortems legitimize expressing doubts without seeming disloyal.
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---
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### Important Decisions
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**Use when:**
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- Stakes are high
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- Irreversible commitments
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- Significant resource allocation
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**Why:**
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Worth the time investment to reduce overconfidence.
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---
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## When Premortems Don't Help
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### Already Uncertain
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**Skip if:**
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- Your probability is ~50%
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- Confidence intervals are already wide
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- You're confused, not confident
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**Why:**
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You don't need a premortem to tell you you're uncertain.
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---
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### Trivial Predictions
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**Skip if:**
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- Low stakes
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- Easily reversible
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- Not worth the time
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**Why:**
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Premortems take effort; save them for important forecasts.
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---
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## The Premortem vs Other Techniques
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### Premortem vs Red Teaming
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**Red Teaming:**
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- Adversarial: Find flaws in the plan
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- Focus: Attack the strategy
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- Mindset: "How do we defeat this?"
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**Premortem:**
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- Temporal: Failure has occurred
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- Focus: Understand what happened
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- Mindset: "What led to this outcome?"
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**Use both:** Red team attacks the plan, premortem explains the failure.
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### Premortem vs Scenario Planning
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**Scenario Planning:**
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- Multiple futures: Good, bad, likely
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- Branching paths
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- Strategies for each scenario
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**Premortem:**
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- Single future: Failure has occurred
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- Backward path
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- Identify risks to avoid
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**Use both:** Scenario planning explores, premortem stress-tests.
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---
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### Premortem vs Risk Register
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**Risk Register:**
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- List of identified risks
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- Probability and impact scores
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- Mitigation strategies
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**Premortem:**
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- Narrative of failure
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- Causal chains
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- Discover unknown unknowns
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**Use both:** Premortem feeds into risk register.
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---
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## Cognitive Mechanisms
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### Why Premortems Defeat Overconfidence
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**1. Prospective Hindsight**
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Imagining an event has occurred improves memory access by 30%.
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**2. Permission to Doubt**
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Social license to express skepticism without seeming negative.
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**3. Concrete Failure Modes**
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Abstract "risks" become specific "this happened, then this, then this."
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**4. Temporal Distancing**
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Viewing from the future reduces emotional attachment to current plan.
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**5. Narrative Construction**
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Building a story forces causal reasoning, revealing gaps.
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---
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## Common Objections
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### "This is too negative!"
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**Response:**
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Pessimism during planning prevents failure during execution.
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**Reframe:**
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Not negative - realistic. You're not hoping for failure, you're preparing for it.
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---
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### "We don't have time for this."
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**Response:**
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- Premortem: 30 minutes
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- Recovering from preventable failure: Months/years
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**Math:**
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If premortem prevents 10% of failures, ROI is massive.
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### "Our case really is different!"
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**Response:**
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Maybe. But the premortem will reveal HOW it's different, not just assert it.
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**Test:**
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If the premortem reveals nothing new, you were right. If it reveals risks, you weren't.
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---
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## Practical Takeaways
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1. **Use for high-confidence predictions** - When you feel certain
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2. **Legitimate skepticism** - Makes doubt socially acceptable
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3. **Concrete failure modes** - Forces specific risks, not vague worries
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4. **Widen confidence intervals** - Adjust based on plausibility of failure narrative
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5. **Set kill criteria** - Know what would change your mind
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6. **Monitor signposts** - Track early warning signals
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**The Rule:**
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> If you can easily write a plausible failure narrative, your confidence is too high.
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---
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**Return to:** [Main Skill](../SKILL.md#interactive-menu)
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