Which statement about planning assumptions is NOT true?

The selection of the statement regarding planning assumptions that is not true highlights the nature of assumptions in a planning context. Planning assumptions are essentially conditions or facts that are taken as true for the purpose of developing a strategy or plan, despite potentially being uncertain or unverified.

While it is important for assumptions to be well-defined, guide the planning process, and be regularly reviewed to adapt to changing circumstances, not all assumptions need to be based on known data. In fact, assumptions often involve forecasting or estimating where data might be incomplete or unavailable; they are used to fill gaps in knowledge to facilitate effective planning. Therefore, stating that they should be known data misrepresents their purpose, as these assumptions can be speculative or based on incomplete information, aimed at anticipating future scenarios and outcomes.