End credits on a large production now run for many minutes and thousands of names. The growth reflects changes in how films are made and who is contractually entitled to appear.
Credit is a contractual entitlement
Screen credit is negotiated in individual contracts and in collective agreements, and it affects future fees, residual payments and eligibility for awards.
Certain credits are governed by union rules that specify wording, order and placement, and disputes over them are resolved through defined procedures.
Because a credit carries real value, removing one is a contractual matter rather than an editorial choice, which pushes the list towards inclusion.
Digital production employs far more people
Visual effects work is labour intensive and distributed across multiple facilities, often on several continents.
A single sequence can involve artists working on modelling, texturing, animation, lighting, simulation and compositing, each a separate specialism.
Where a film once listed an optical effects unit of a few dozen, a comparable production now lists hundreds of individually named artists.
Production is spread across countries
Filming incentives are offered by many jurisdictions, and they generally require that local crew be employed to qualify.
A production shooting in several territories therefore builds a separate local crew in each, and every one appears in the credits.
The same applies to post-production, which is frequently placed where the incentives are strongest rather than where the shoot occurred.
Music and licensing add their own blocks
Every licensed track carries required credit wording for writers, publishers and performing rights bodies, agreed as part of the licence.
Score credits extend to orchestrators, copyists, engineers and the musicians on the recording, each with their own conventions.
These blocks are contractual in the same way as crew credits, and their length is set by the licence rather than by the production.
The length has practical consequences
Long credits reduce how many screenings a cinema can fit into a day, which is a real cost across a wide release.
They have also changed audience behaviour, since scenes placed after the credits give viewers a reason to stay through them.
Some productions now split credits into a short opening block and a longer closing one, or use a faster crawl and multiple columns, but the underlying obligations are unchanged and the totals keep rising.
Because so much of the list is contractual, the length of a film's credits has become a rough indication of how distributed its production was rather than of how large its budget happened to be.