Video review was introduced to correct clear mistakes. In practice it altered the structure of officiating itself, and several of the effects were not anticipated.
Review is limited by design
No sport reviews everything. Each defines a set of reviewable situations, typically decisions that are factual, discrete and consequential enough to justify stopping play.
Judgement calls that depend on interpretation are usually excluded, because reviewing them would replace one opinion with another rather than correcting an error of fact.
Where the boundary sits is contested in every sport that uses review, and it is redrawn frequently as officials and competitors test its edges.
The threshold matters more than the footage
Most systems require clear evidence before an on-field decision is overturned, meaning ambiguous footage leaves the original call standing.
This produces outcomes that look inconsistent to viewers: two apparently similar incidents are decided differently because one had a usable camera angle and the other did not.
The standard exists to keep the on-field official's judgement as the default, but it means the original call still determines the result in genuinely unclear cases.
Precision exposed the rules themselves
Freezing an image to determine position revealed that some rules had never been written with that resolution in mind, having previously been applied by naked-eye judgement.
Offside decisions are the clearest example, where frame-level analysis produces margins far smaller than the rule's drafters would have contemplated.
Several sports have since amended the rules themselves, adding tolerances or redefining reference points, because the measurement technology had outrun the wording.
Delay has its own cost
Stopping play to review interrupts the rhythm of a contest, and the interruption is experienced very differently by a stadium crowd than by a television audience.
Spectators at the ground often lack the footage being examined and wait without information, which is why many competitions now show the review process on screens.
Time limits and centralised review rooms are attempts to reduce the delay, trading some thoroughness for a pace closer to the unreviewed game.
Authority moved off the field
The most durable change is structural. A referee who once held final authority now shares it with officials watching remotely.
That shift alters how players behave, since appealing to the review system becomes a tactic and the on-field official is no longer the last word.
Whether the accuracy gained is worth the authority dispersed remains genuinely disputed among administrators, players and supporters, and the answer differs by sport.