Roll-forward

How to use the concept

Use roll-forward as a lens on the delivery system rather than as an isolated score. Segment by service, environment, release path, and change type when those distinctions affect risk or waiting. The same label can describe different operational realities if teams do not document the counting rule.

A concrete delivery example

Suppose a service records 100 relevant events during a month and 8 meet the condition represented by roll-forward. Under that explicit rule, the reported share is 8 percent. The team then reviews the eight cases individually, because the aggregate says how often the condition appeared but not why it appeared.

Limitations and interpretation

The main limitation is scope. Roll-forward does not by itself establish customer value, code quality, developer well-being, or causation. A change can improve this signal while shifting risk into another stage, so pair it with compatible delivery and reliability evidence.

Before acting on roll-forward, compare the current observation with a compatible baseline and ask which underlying event produced it. Keep the raw records, counting policy, and ownership visible. When the signal changes, inspect the surrounding workflow for queueing, rework, failed checks, or recovery work. That practice makes the glossary term useful for diagnosis rather than a label attached to a dashboard.