A review of a film written on release still describes that film a decade later. A review of a game often describes something that no longer exists within weeks.
One product is fixed and the other is not
A finished film is locked. Barring an alternate cut, the object a critic assessed is the object anyone will encounter later.
A game continues to be developed after release, and patches change performance, balance and sometimes structure.
The review therefore describes a snapshot, and nothing in the format makes clear how long that snapshot remained accurate.
Reviewers play a version that briefly exists
Review builds are distributed before release, frequently without the patch that arrives on launch day.
Problems a reviewer describes may already be fixed by the time a reader can buy the game, and problems introduced later were never assessed.
Careful outlets state which build they played and whether they had the launch patch, which is the only way the reader can calibrate.
Performance is the most volatile element of all, since a frame rate measured on a pre-release build can improve or degrade with any subsequent update.
Servers make the experience unrepeatable
Anything with an online component is reviewed under artificial conditions, on servers populated by other reviewers rather than by players.
Queue times, matchmaking quality and the behaviour of a live economy cannot be evaluated before a real population arrives.
This is why many outlets now publish an initial assessment and revisit the game once servers are public, treating the review as a process.
Balance changes rewrite the subject
A competitive game adjusted repeatedly after release may play quite differently from the version described, with strategies that no longer function.
Live service titles go further, adding modes and reworking systems until the game shares little beyond a name with its reviewed form.
A review of such a game is closer to a report on an opening night than to an assessment of a finished work.
The reverse also happens. Games released in poor condition and repaired over a year end up with a public record written entirely from their worst month.
Why the score stays anyway
Scores are rarely revised, because aggregation systems record the original figure and outlets have limited appetite for repeating work.
The number therefore persists as the permanent public verdict on a moment that has passed.
Games that improved substantially carry a low figure indefinitely, and games that degraded keep a high one, which is a defect in the format rather than in the criticism.