Too true. Today when Google's App Engine failed hard, they flat out said: "App Engine is currently experiencing serving issues – Python, Java, Go … Oct 26 2012, 07:30 AM-11:59 PM … Current Availability: 55.90%" and showed read/write I/O metrics were spiking through the roof. Their dashboard clearly labeled the relevant icon as the most severe "Service Interruption".
You left out "Green if everything is working - except the Chaos Monkey. All systems are working properly, but none of them failing randomly 'for your convenience'"
Green if everything is fine. Green if there are intermittent problems. Green if nothing works.