Predecessor Interview Planning
Plan with lessons from people who have already traveled the road
- Difficulty
- Easy
- Time to result
- ~days to results
- Steps
- 5
- Confidence
- 94%
People commonly plan from the inside: they focus on what they intend to do and imagine the steps proceeding as expected. This neglects external pressures, hidden difficulties, and tactics that are obvious only after experience. Predecessor Interview Planning corrects that bias by consulting people who have already attempted the same journey. The planner gathers unexpected obstacles, realistic effort estimates, failure patterns, and proven responses, then uses that evidence to revise the plan. The output is not blind imitation but a better map of the problem space, including contingencies for uncertainties that remain. The method is especially useful for difficult personal changes, long projects, and ventures where optimism tends to compress schedules and inflate expected results.
Origin
David Dunning proposed interviewing people who had attempted the same goal as an antidote to failed resolutions and overly optimistic planning. Extracted from Masters in Business.
Core principles
- 01Intentions do not reveal every obstacle.
- 02Unknown unknowns weaken inside-view planning.
- 03Prior practitioners hold practical knowledge you lack.
- 04Failed attempts reveal barriers as well as successful tactics.
- 05Plans improve when outside evidence changes assumptions.
How to run it
- 1
Define the Comparable Journey
Describe the goal, starting conditions, constraints, and intended outcome. Use these details to identify genuinely relevant predecessors.
Pro tip Seek people whose resources and circumstances resemble yours.
Watch out Advice from an superficially similar but structurally different situation may mislead.
- 2
Recruit Varied Predecessors
Talk with people who succeeded, struggled, and quit. Their combined experiences reveal both effective tactics and common failure modes.
Pro tip Include at least one person whose attempt failed despite strong intentions.
Watch out Interviewing only visible winners creates survivorship bias.
- 3
Probe for Surprises
Ask what proved harder, slower, or more expensive than expected. Identify external forces and unknowns that their original plans missed.
Pro tip Ask what they wish they had known before starting.
Watch out Generic encouragement is less useful than concrete incidents.
- 4
Extract Tested Responses
Collect the strategies, routines, resources, and contingencies that helped them handle real obstacles. Note the conditions under which each tactic worked.
Pro tip Prioritize repeated lessons reported by several people.
Watch out Do not copy tactics without checking whether their enabling conditions apply.
- 5
Rebuild the Plan
Update the schedule, effort estimate, milestones, and risk controls using the interview evidence. Explicitly reserve capacity for unknown unknowns.
Pro tip Document which assumption each external lesson changed.
Watch out Consultation has no value if the original plan remains untouched.
In the wild
Someone planning a strict January fitness routine interviews a long-term exerciser, a person who repeatedly quit, and a coach. They discover that travel, soreness, scheduling, and all-or-nothing goals cause more failures than lack of motivation. The plan is rebuilt around shorter sessions, fallback workouts, and gradual progression.
→ The resolution becomes resilient to predictable disruptions rather than depending on perfect motivation.
A founder interviews operators who launched similar products and learns that integration testing, support preparation, and customer onboarding consumed more time than development. The founder expands the schedule and creates contingency milestones before announcing a date.
→ The launch estimate reflects observed bottlenecks rather than the founder's optimistic scenario.
Common mistakes
Using Only Yourself as the Expert
The plan is built entirely from personal intentions even though the planner lacks experience with the road ahead.
Interviewing Only Winners
Successful examples may hide common barriers and produce an unrealistically clean picture of the journey.
Collecting Advice Without Revising
Insights are gathered but never translated into changed assumptions, resources, or contingencies.
Is it for you?
Best for
It is best for unfamiliar projects, behavior changes, and goals that others have attempted before.
Not ideal for
It is not ideal when the task is genuinely unprecedented and no relevant predecessor experience exists.
From the transcript
“What we really should do is interview people who tried to do this before and find out what the real difficulties are.”
“They're gonna be many difficulties that we haven't anticipated they're gonna be many difficulties that we don't know about.”
“It's good to consult, It's good to find out who's had a success. It's good to confer with other people.”
From the episode
David Dunning on the Dunning-Kruger Effect
David Dunning