The 70 Percent Decision

Why it works

A prediction error can be closed in two ways: the internal model is adjusted, or action is taken to align the world with the model. Waiting alone resolves nothing – it merely postpones the choice between those two paths.

Resilient organisations facing radical uncertainty do not wait for complete clarity. They pursue several paths in parallel and adapt their course dynamically instead of committing prematurely – or not committing at all (Bastian et al., 2025).

A longitudinal study with project managers shows that ambiguity tolerance is not a fixed personality trait but a trainable state. The extent to which someone can tolerate uncertainty fluctuates from week to week and is closely related to performance and wellbeing (O'Connor, Wiewiora & Spark, 2024). An earlier study by the same research group also found that leaders with greater ambiguity tolerance have a measurable positive effect on employee performance (O'Connor, Jimmieson, Bergin, Wiewiora & McColl, 2022). The 70 percent threshold in this exercise is not a scientific cut-off; it is a practical rule of thumb that makes the training tangible.

At a glance

How to proceed

1. Choose a real decision

   Use a genuine decision that is currently pending, not a hypothetical one. This is essential; otherwise the exercise has no consequences.

2. Fill the three columns

   What do I know with certainty about this decision? What do I assume without being able to prove it? And what do I simply not know? Make sure assumptions do not slip into the first column; that is where most false certainties hide.

3. Estimate your clarity

   Be honest: if 100 percent represented complete clarity, where are you now?

4. At 70 percent or more: decide

   Formulate the decision you would make at this level of clarity. Immediately agree on a fixed review date – not “sometime”, but a specific date.

5. Below 70 percent: shift the focus

   Ask which missing percentages could actually be clarified by waiting and which can only be clarified through action. Develop one or two parallel paths that can be pursued simultaneously instead of waiting completely.

Reflection questions

Give these questions deliberate time – ideally in writing, alone or after the exercise.

1. What really prevents me from deciding with 70 percent clarity instead of waiting for 100 percent?

2. What changes in my body when I allow myself to work with an assumption rather than certainty?

3. Which of the missing 30 percent could only be clarified through action, not by waiting longer?

4. Whose expectation of “certainty before deciding” am I trying to meet?

5. What is the highest price if I decide now and turn out to be wrong?

6. What is the highest price if I do not decide at all?

7. Which parallel path could I keep open instead of committing prematurely to one route?

8. How will I know in four weeks whether this decision was right, and who sets that review date?

9. How often have I waited for 100 percent in the past, and what did that cost me?

10. What would a leader I admire do in my place with exactly these 70 percent?

What people often discover

The most common insight is that the cost of waiting had previously been invisible; explicitly asking about it makes it tangible. Many people recognise that a substantial proportion of the missing information would never become clear through more thinking, only through a first step. The distinction between “know” and “assume” is also often surprisingly revealing: many supposed facts turn out to be unspoken assumptions.

For everyday use

The 70 percent principle can become a fixed decision rule within a team, combined with a binding review date instead of endless adjustment. Even the language – “We are at 70 percent; we decide now and review in four weeks” – noticeably reduces decision pressure because it acknowledges fallibility from the outset rather than suppressing it.

Variants