Five stages, and the one that actually costs you money
A maturity model is only useful if it tells you which single step to take next. Most estates are at stage two and think they are at stage four.
Stage 1 — Files
Forms live in folders. Identity is a filename. Nobody can say what is in production without looking at production.
Stage 2 — Inventoried
There is a list, and it is out of date. Dependencies are known to individuals rather than recorded. This is where most estates sit.
Stage 3 — Identified and versioned
Every asset has durable identity and immutable revisions. The question "which version is live" has one answer. This is the step that pays for itself, because every later capability depends on it.
Stage 4 — Validated and reviewed
Changes are checked automatically and approved against specific revisions. Exceptions are recorded waivers with owners and expiry dates.
Stage 5 — Released and reversible
Production is a reproducible manifest, promotion is gated, and rollback is routine. At this point a renderer upgrade is a scheduled run rather than a programme.