Winch setup/kill switch

I am looking to install a winch and am reading up on how to wire it. I see a lot of people say it needs to be fused next to the battery just like anything else. But then I also see that a 12K can draw as much as 485 amps at times. So, kind of an academic question... If the winch gets fused with a 500 amp fuse for it's potential max draw, what is the fuse protecting? What malfunction condition will cause more amp draw than the winch does when it's operating. I understand that we fuse wires coming off the battery in case of shorts or to keep the wire from melting and starting a fire in case of an overdraw(how ever that's supposed to happen). But with a 2 gauge power cable and a 500 amp fuse, what malfunction would have to exist to make that fuse do its job and blow? If it's a runaway winch somehow just set on spontaneous combustion, that thing would have to be F'd anyway right?

And would a circuit breaker work better for this application since it would protect the battery and line but also serve as a power switch to prevent drain when the winch is not in use?