Everyone comes up with their own solutions to predators. I have a sturdy enclosed coop for nighttime, and a large run on a sloped mountainside. The fence is tall, but certainly not strong enough to keep out a bear or a mountain lion if they really wanted in (lions can jump something like 12 feet?) We have a dog that is in charge of barking off bears, mountain lions, bobcats, and hawks. I am open to the idea of hot wire, but haven't felt like we needed it yet, because the dog is really effective. We still lose some chickens each year, mostly to birds of prey. I swear the goshawk watches until the dog gets in the car with me and leaves her post. Having some cover for the chickens to hide under helps.
My neighbors, on the other hand, have a fort knox style coop and run, 100% enclosed in chain link, including the top, with padlocks and hot wire.