Brief
The essential idea
The chapter uses a geometric metaphor to show what happens when success requires simultaneous compliance with many independent criteria. If the inner ninety percent counts as acceptable in one dimension, it occupies 90 percent; in two dimensions it occupies 81 percent; in three, 72.9 percent; and in one hundred dimensions, 0.9 to the power of 100 is only about 0.0027 percent.
Even a one-percent tolerance on every criterion yields only about 36.6 percent in one hundred dimensions. The calculation illustrates why a binary verdict becomes increasingly hostile to workable projects as criteria multiply: a small miss on one dimension can erase all value created elsewhere.
The alternative is not to abandon standards. Leaders should distinguish global outcomes from local criteria, define tolerance zones in advance, use graded scales, and test whether component measures correlate with the result that matters. Time, budget, and initial scope are insufficient if they obscure delivered business value.
Decision lens
Key takeaways
Requiring strict success on every dimension makes aggregate failure mathematically more likely as criteria multiply.
A binary verdict hides the size and practical importance of each deviation.
Small misses should not automatically erase value produced on other dimensions.
Tolerance zones must be agreed before results are known, not negotiated after the fact.
Graded scales reveal signal strength better than a single yes-or-no classification.
Local measures should be tested for correlation with the desired business outcome.
A project can miss its original plan and still create value, or meet the plan while failing the real goal.
Workplace experiment
Apply it at work
- 1
Separate the primary business outcome from supporting delivery and quality criteria.
- 2
Define an acceptable range and relative importance for each criterion before evaluation.
- 3
Replace one binary project-health measure with a graded scale that exposes the size of deviations.
- 4
Review whether local success measures actually correlate with the outcome used to judge the initiative.
Choose one action, define the observable effect, and keep the first test small enough to reverse.
Evidence
Sources and further reading
Primary source
Additional sources
Channel, aggregator, and commentary links confirm the work; they are not the primary source.