The safety buffer allows for errors in the air by including an additional area that a pilot might stray into by flying off track.
By flying at or above this altitude a pilot complies with terrain clearance requirements on that particular flight leg.
The AMA is the lowest off-airway altitude to be used under instrument meteorological conditions (IMC) that will provide a minimum vertical clearance of 1,000 feet (AGL), or in designated mountainous terrain 2,000 feet above all obstacles located in the area specified, rounded up to the nearest 100 foot increment.
Instead, a VFR flight can be conducted using pilotage, watching landmarks to determine position and desired direction.
Pilotage in the United States is usually accomplished with the use of sectional charts, which show the ground with considerable accuracy, both for terrain levels and for man-made objects.