What is the advantage of having muscles that run at different angles in the stomach?

The stomach has three layers of smooth muscle fibers run in three different angles. These layers are critical in giving the stomach the capability to mix, well, ingested food as it is mixed with enzymes and hydrochloric acid. This is important because smoothe muscles can only contract in one direction hence the layers give multidirectional movements of the stomach hence goof mixing and better digestion.