Name the assumptions that must hold for the plan to work

Every plan rests on assumptions — list them and ask how likely each one is.

Why it works

Plans fail when hidden assumptions are violated. Making assumptions explicit converts them from invisible background beliefs into testable hypotheses with associated probabilities. This allows you to assess how sensitive the plan is to each assumption — whether failure of one assumption kills the plan or just reduces its upside.

How to do it

1. Write down the plan, then ask: what would have to be true about the world for this to work?
2. List every major assumption, including "no major unexpected disruptions."
3. Estimate a probability for each — not precisely, but whether it is 90%+, 60–90%, or below 60%.
4. For any assumption below 80%, ask what the plan looks like if that assumption fails.

Evidence

Assumption-surfacing is a core step in scenario planning, risk analysis, and prospective hindsight (premortem) techniques. Explicit articulation of plan dependencies improves risk awareness and plan quality in practitioner frameworks. (clinical)

Direct experimental evidence on assumption-listing as an isolated practice is limited; the benefit is principled from the broader evidence on planning under uncertainty.

Common mistake

Listing assumptions and then not checking whether any of them are already contraindicated by existing evidence.