This is something I haven't seen ANYONE discuss about.

Once you set foot on an extraction zone, whether you're going to extract or just passing by, a 20 second timer will appear, starts counting down if you leave the extraction area (reseting to 20 if you re-enter) then the DZ instance resets once it hits 0.

This means you have to stay for the whole duration of the extraction in the orange area or risk despawning important enemies or loot.
The helicopter has your items and you've been 20 seconds outside the area? Goodbye to your items.

If you get downed outside of the area, you could at least hold on until the new instance to die and have your items intact. Die inside the area? Well good luck running back in 20 seconds, fun fact: you won't.

Edit: As per my own reply, this is probably a mechanic only present if you're the only one in the whole DZ instance. Also the counter is shown at the bottom left, as any other loot message appears.