The technical run is the rehearsal that saves the event

A separate, unhurried technical run catches the failures that cannot be fixed live.

A technical run is not a content rehearsal, and conflating the two is why it gets skipped. Its purpose is to exercise every mechanical thing that must work on the day, in the same conditions as the day: the same room, the same connection, the same equipment, the same accounts, the same people in the same roles. Everyone joins as they will join, shares what they will share, plays whatever will be played, and hands over to each other exactly as planned.

The value is in the discoveries. The shared material that looks fine locally and unreadable to everyone else. The speaker whose audio is fine alone and echoing when a second person joins. The handover that requires a permission nobody has. The recording that starts when someone remembers rather than when the session does. None of these are exotic, all of them are ordinary, and every one of them is a live disaster and a trivial rehearsal note.

Run it far enough ahead to fix what it finds, which usually means days rather than the hour before. Write the outcome as a short sequence of who does what and when, and keep it visible to the crew during the session. Then hold a brief check on the day for the things that change overnight, and agree in advance what happens if something fails anyway: who speaks, what is said, and how long you wait before moving to the fallback.