Florence Nightingale’s coxcomb diagram

the backlog problem: data exists, action doesn’t

In 1854, Florence Nightingale arrived at a British military hospital in Scutari during the Crimean War. Military leaders believed battlefield injuries were the primary cause of death. What Nightingale found was something very different.

Far more soldiers were dying from infection, poor sanitation, and contaminated water than from combat wounds. The causes were consistent and largely preventable. She began documenting everything she could: causes of death, ward conditions, sanitation practices, and outcomes tracked month by month.

The evidence was clear. It still did not lead to change.

Reports were written and figures were shared, but nothing forced the issue. The problem was not that the data was wrong. It was that the data did not compel action from the people who had the authority to act.

the signal leadership could not interpret

Nightingale realised that the issue was not the numbers themselves, but the effort required to understand them. Tables and summaries demanded interpretation, and interpretation created distance. As long as the scale of the problem felt abstract, it could be debated, delayed, or quietly ignored.

She addressed that by changing how the same information was presented.

The coxcomb diagram removed that distance. By showing deaths over time and separating them by cause, it made the pattern obvious at a glance. Disease accounted for the vast majority of mortality. Combat deaths barely featured.

When this was presented to Parliament, the discussion moved quickly from argument to response. Hospitals were redesigned, sanitation standards were enforced, and mortality rates fell. The underlying data had not changed. What changed was the ability to see it clearly.

why this still matters

The wider impact of Nightingale’s work extended well beyond the Crimean War. It helped establish the foundations of modern public health, where data is used not simply to record outcomes, but to shape decisions before more harm occurs.

That lesson has not aged.

Most organisations today are not short on data. They are short on coherence. Support tickets sit in one system, product signals in another, account context in someone’s head. Each view is locally accurate and globally incomplete.

Risk develops gradually across those gaps. Accounts decline without a single dramatic failure. By the time the issue is obvious to everyone, it is usually expensive to fix.

the modern equivalent of the coxcomb

This is the gap Signals is designed to close.

Signals is not about producing more dashboards or more metrics. It is about making patterns visible early enough to act. It aims to be the modern equivalent of Nightingale’s diagram: a living view of your customer base that surfaces emerging risk, explains why it is happening, and makes the next action clearer.

Nightingale did not drive change by collecting more data. She drove change by making the truth easier to see than to ignore.

When teams can see what is actually happening, they tend to act sooner. When they act sooner, outcomes improve.

See risk early. Act faster. Keep revenue green.

decision making

Florence Nightingale’s coxcomb diagram