From the initiation of the preflight process through the securing of the aircraft at the end of the flight, there are hundreds of decisions to be made and actions to be taken, ranging from weather interpretation, fuel uplift and route of flight selection to the operation of the aircraft and its systems to the navigational aspects of the flight. Proper procedures must be observed and executed to complete the flight safely and ensure no hazard is created to the aircraft in question or to other aeroplanes in its proximity. Obviously, anything that impairs a pilot's ability to make decisions or execute the associated tasks will increase the potential for an accident or incident.