In a perfect world, software functions as it should with no unintended side effect. But we do not live in a perfect world and it isn't rare that an update would wreck havoc on devices that run them. Rare, however, are times when software wrecks havoc even without a software update or similar. That is apparently the nightmare that greeted Google WiFi and OnHub owners when the routers, for no apparent reason, suddenly refused to connect through no fault of their own. This time, it is totally Google's fault and it admits it.