An event is a temporary organisation built to dissolve
Everything that makes ordinary organisations work, accumulated relationships, learned processes, redundancy in people, is unavailable. The whole thing is assembled and then taken apart.
A permanent organisation runs on things nobody notices. People know each other. Processes have been through several iterations. When somebody is absent, another person knows enough to cover. Mistakes surface over weeks and are absorbed. An event has none of that. It brings together contractors, volunteers, venue staff, performers and suppliers who have frequently never worked together, to execute something once, at a fixed time, in front of an audience, with no possibility of postponement once it has begun.
That structure explains most of what is distinctive about the work. Communication has to be explicit, because nothing can be assumed to be understood. Documentation matters more than in ordinary operations, because the knowledge lives in a temporary team. And single points of failure are everywhere by default, since almost every role is held by one person who has not done it here before.
The second structural feature is that the schedule is immovable. Almost every other kind of project can slip. An event cannot: the doors open at the advertised time whether or not the work is finished, and the consequence of being behind is not a delayed launch but a visible failure in front of the audience and, in some circumstances, a genuine safety problem.
This is why experienced event people are preoccupied with things that look excessive from outside. They want the schedule to have slack in it, because there is no way to recover it later. They want to know who makes each decision on the day, because a decision that has to be escalated during an event does not get made. They want the contingency plan written down rather than discussed, because the person who will need it may not be the person who discussed it.
The third feature is that the failures that matter most are not the ones the audience notices. A poor sound mix is embarrassing. An entry point that becomes congested, an evacuation route obstructed by a supplier's truck, or a medical incident with no clear response is a different category of problem, and it is produced by the same planning process that produced the running order.
Crowd management deserves particular emphasis because it is the area where consequences are most severe and where the discipline is least visible to the public. The serious incidents at large gatherings, historically, have overwhelmingly involved crowd density and movement rather than any of the things audiences worry about, and they have generally been foreseeable from the layout and the schedule.
None of this makes large events dangerous or unmanageable. They are run competently at very large scale constantly, by people who have made the planning unremarkable. The argument is that the competence is invisible by design, that it lives in the unglamorous parts of the work, and that events go wrong when the effort concentrates on what the audience will see.
One further observation about how these projects are staffed, since it explains a recurring pattern. Event work attracts people who are good in the moment: quick, calm under pressure, able to solve a problem with what is available. Those are genuinely valuable qualities and they are not the same as the qualities that prevent the problem, which are methodical, unglamorous and exercised months earlier. A team composed entirely of excellent improvisers will produce an event that runs and will have spent the day solving things that a duller person would have prevented in March.