I worked at a wireless telecom company 10 years ago. The local switches did not have a consistent decom procedure. One switch removed two routers and had it on a truck to leave that was used for a critical service all within a few hours. It would have taken a week or longer to fix if we were not able to get it off the truck and put back into the rack. We then forced all regions to have a 10 day policy of powering off a device 10 days before they remove any cabling or the device it self.