The defense (DEF) readiness condition (CON) is an alert state used by the United States Armed Forces. DEFCON 5 is the condition denoting normal readiness, going up to DEFCON 1 which signifies maximum readiness.
Similarly, driver training in Europe emphasizes always having a high state of readiness. I passed my driving test in the UK for both motorcycles and cars and have ridden mopeds and motorcycles since I was 16 years old (the UK tests are among the toughest in the world). Expecting the unexpected is my driving life mantra.