"The greater part of valor is discretion"

Sometimes, it becomes more important to make wise choices than to act valor.
Valor does not mean to fight without strategy as it will not bring victory but defeat, therefore before taking any decision or performing valor act choices are necessary to be made.
Nations, having enough courage and strength when fight without any plans face defeats. Similarly, when a business man who do not have proper market analysis invests in market will definitely bear loss.
History is full of a host of examples. USA which became super power after World War-II face severe defeat at the hand of Vietnam. Reason behind USA's defeat was that it underestimated Vietnam. On contrary, when Vietnam fought against USA with perfect planing achieved victory which proves that some time wise choice are necessary rather acting valor.
Though it is better to be discrete, but in situations like emergency and terrorist attacks one has to respond quickly because in such situations one does not have enough time to make choices and further delay could result in catastrophic destruction.