Mine postmortems for repeated failure patterns

When it fits

• Individual incidents are being closed but similar failure modes keep returning under different names.

When to avoid it

• Do not copy another organization's incident frequencies as your baseline or force every event into a convenient category.

Why it matters

Periodically classify incidents by trigger, contributing conditions and affected system patterns using a small local taxonomy. Look for concentrations that justify a shared fix: deployment checks, interface design, capacity controls, observability or ownership. Keep the raw incidents visible so the categories do not become a substitute for reading the evidence.

Steps

1. Choose a small set of locally meaningful trigger and contributing-factor categories.
2. Classify a bounded period of postmortems consistently.
3. Identify repeated patterns with enough examples to inspect.
4. Create one systemic improvement hypothesis and test whether future incident data changes.

Check your result

The analysis produces a cross-incident improvement target supported by identifiable incident records.

Keep this limit in mind

• Do not copy another organization's incident frequencies as your baseline or force every event into a convenient category.