The history of media embargoes as a professional convention
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The embargo developed as a practical compromise between organisations wanting simultaneous coverage across multiple outlets at once and journalists needing genuine time to research and write a properly considered story rather than a rushed one produced under pressure. It offered both sides something neither could easily get without the other's willing cooperation.
Over time, the embargo became a widely understood professional convention across the industry, resting entirely on mutual trust rather than any formal enforcement mechanism whatsoever. A journalist who broke an embargo risked being excluded from future opportunities entirely, which gave the whole system enough real weight to function reliably across an entire industry for many decades.
The convention has had to adapt considerably as publishing itself has sped up and diversified across countless new platforms. Instant digital publication made embargo timing far more precise and, at the same time, far more easily broken than it ever once was. Even so, the underlying logic, trading advance access for coordinated, considered coverage, remains largely unchanged today.