Challenges for a marine are constant, a challenge is actually life in itself. However one challenge a marine faces in combat is friction. Within friction is the physical enviroment, nature of a mission, and inadequate information; these cause uncertainty or otherwise said, the fog of war. Also maintaining a moral standard affects unit cohesion. Subordinates must feel that a leader genuinly cares for them, and that they are fighting for a worthy cause. Added to these challenges is a physical demand which affects the mental stability of all. Some examples are sleep deprivation, poor diet and hygiene. No one is immune to fatigue; but endurance can be increased so that it is not reached as quickly. Many with confidence in their abilities and endurance
