A go-around occurs when an aircrew decides not to continue an approach, or not to continue a landing, and follows procedures to conduct another approach or to divert to another airport. Go-arounds may also be directed by Air Traffic Control (ATC) due to runway conflicts or a variety of other reasons. They can happen at any point from the final approach fix to wheels on the runway (but prior to any deceleration device being activated - e.g. brakes, spoilers, thrust reversers). Each go-around has its own unique challenges.