Can you give me example about planning may create rigidity?

formal planning efforts can lock an organization into specific goals to be achieved within specific timetables. When these objectives were set, the assumption may have been made that the environment wouldn't change during the time period the objectives cover. If that assumption is faulty, managers who follow a plan may have trouble. Rather than remaining flexible- and possibly scrapping the plan-managers who continue to do what is required to achieve the original objectives may not be able to cope with the changed environment. Forcing a course of action when the environment is fluid can be a recipe for disaster.

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