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FIELD GUIDE #003 // PRIORITIZE

Pareto AnalysisPrioritize the problem before explaining it.

Pareto Analysis ranks recurring categories by one consistent measure — incidents, defects, downtime, cost or another impact metric — so attention starts where the largest share of the observed burden sits.

USE WHENYOU HAVE REPEATED CATEGORY DATA
AVOID WHENTHE CATEGORIES USE INCOMPARABLE MEASURES
REMEMBERPRIORITY IS NOT CAUSALITY

WHAT PARETO ACTUALLY TELLS YOU_

Rank the categories from largest to smallest and calculate their cumulative share. The shape tells you whether impact is concentrated in a few categories or spread more evenly.

CAPYBARA RULE: Pareto answers “where is the recurring impact concentrated?” It does not answer “why is this happening?”

USE COMPARABLE DATA_

01Define the analysis. Use one time window and one population.
02Choose one measure. Do not mix frequency for one category with cost for another.
03Group consistently. Define categories consistently and avoid counting the same incident twice.
04Rank and cumulate. Largest first, then track how quickly the cumulative share grows.
05Choose what to investigate. Use the ranking to focus causal work, not to declare a root cause.

CAPYBARA CASE #003_

The Chaotic Capybara Café logged 100 incidents:

DROPPED WATERMELON42
COLD COFFEE25
MISSING SPOONS13
LONG QUEUE9
WRONG ORDER7
CHAIR SQUEAK4

The top three categories account for 80% of the incidents. That is a strong prioritization signal. It still says nothing about why watermelon gets dropped or coffee gets cold.

COMMON FAILURE MODES_

Treating 80/20 as a law

The classic pattern is a useful heuristic, not a requirement. Your data may be more or less concentrated. The workspace lets you inspect a threshold rather than worship one ratio.

Mixing measures

Ten expensive failures and ten minor complaints are not comparable if one row means cost and another means count.

Using tiny or unstable samples

A ranking from a handful of events may move dramatically next week. Record the time window and data quality.

Confusing frequency with severity

The most frequent category is not automatically the highest-risk category. Choose the measure that matches the decision you need to make.

HAND THE PRIORITY TO A CAUSAL TOOL_

Once the highest-value category is clear, take that category into Fishbone to map competing causes or into 5 Whys when a coherent causal chain is already plausible. That handoff is where prioritization becomes investigation.

GOOD CHECK: If you ranked total downtime instead of incident counts, would you still choose the same priority? If not, be explicit about why this measure is the right one.

OPEN PARETO →USE IN AN INVESTIGATION →