The more redundant you are the more it costs. And even with redundant network routes, power distribution, backup generators there always seems to be an undiscovered SPOF left.
Murphey's Law is the Law of the Universe ;)
One hosting provider I used, I forget who, had redundant everything, except some part of the power switching to the UPSs. During a regular UPS maintenance test it failed and half their datacenter went dark.
I visited Savvis hosting facility several years ago and they had redundant generators (each about ths size of my two car garage), redundant network connections (some high-level peerage), two separate power lines from isolated parts of the grid, and at least two separate certified diesel suppliers. Oh, and VESD fire detection and grate-type floors to help with the cooling.
every reasonable co-lo has redundant power and redundant bandwidth. hell, even tiny guys like me have that.
Most co-lo power outages are not due to both incoming power feeds failing; usually it is either human error or failure in the power equipment that is not redundant enough. It happens even at the best data centers.
Most network outages, on the other hand, are caused by human error. it's not very difficult to make your network extremely resilient to upstream failures; Even the smallest ISP is going to have more than one upstream. however, if you give the new guy access to the BGP routers, (or the old guy, when he hasn't had enough sleep) it's not at all difficult to break the whole thing.
Murphey's Law is the Law of the Universe ;)
One hosting provider I used, I forget who, had redundant everything, except some part of the power switching to the UPSs. During a regular UPS maintenance test it failed and half their datacenter went dark.