What happens if the door closes at night and one or more chickens aren't already inside? Is that a thing that happens? Do they pretty much always go inside at the same time every evening? Is it bad if one gets left out alone?
If a chicken isn't in the coop by the time the sun is setting, then they don't want to be in the coop and you would have to manually intervene anyways. It's always the same chicken(s) too. They want to roost in a tree or on the roof or something. If one of your chickens develops this habit, the best way to break it is to keep them locked in the coop for a few days as soon as you realize what's happening.
But barring that situation, chickens always go in the coop. I can tell it's 15 minutes to sunset when the chickens start ambling up the ramp.
It wasn't really an issue, They'd go in between sunset and one of the twilight light levels, and that was that. When we did it without the automatic door, there was a lot more chasing type manual labor just getting them in if it was early, or we'd forget and it would be super late.
Didn't ever lose one at night, but there were definitely daytime predators that were an issue. (mainly raptors)
I know nothing about chicken coops.