While versatility focuses on the right organization and equipment, agility is about people, leadership and training. Future forces must be more adaptive to both different and changing situations. These forces must have utility across the spectrum. In fact, they must be fungible. Further, versatility will allow forces to adapt quickly to changing requirements within a commitment.
Crises often mutate with little warning.
Forces must be prepared to accommodate those changes in stride. Experience has proven that we will rarely have time to organize and prepare forces to respond specifically at various points across the spectrum of operations. Therefore, we must build-in the organizational flexibility to respond. Similarly, the post-Cold War downsizing has left us with too few numbers of forces to specialize too greatly. Force robustness lends an inherent quality to responsiveness.