Patton argues that effective planning begins with the situation as it actually exists. A commander may have preferred objectives or methods, but those plans must be adjusted when terrain, enemy movements, available forces, supply conditions or other circumstances change. Trying to force events to conform to an earlier plan can create unnecessary risk and reduce the ability to respond to new information.

The quotation emphasises flexibility without rejecting planning itself. Patton’s point is that plans should provide direction while remaining open to revision as conditions develop. In military operations, where circumstances can change quickly, success may depend on recognising when an assumption is no longer valid and altering the plan accordingly. The broader lesson is that preparation is most useful when it supports sound judgement rather than becoming a rigid commitment to a course of action that no longer fits the facts.