this is really a management decision - if you don't supervise, you may have more losses to predators - it depends on how your facility is, perimeter fencing, what kind of predators you have...
we're on 40 acres, our birds free range during the day, they are not supervised. they put themselves up at night, although we're changing their coop so for the next couple of weeks I need to be there before dusk to get them in the new habit. we have LGDs, but they're not currently running the same field as the birds. we do have coyotes, so everyone is in at night. we do know that we could lose birds. we've lost 2 chickens to hawks, but so far that's all.
some folks keep their birds in fully covered pens, others free range with supervision, some just free range. you have to decide what you're comfortable with.