I returned, and saw under the Sun, that the race is not to the swift, nor the battle to the strong, neither yet bread to the wise, nor yet riches to men of understanding, nor yet favour to men of skill; but time and chance happeneth to them all.
The math of evaluating costs against benefits doesn't always give us the right answer. If it did, the race would always be won by the swift, the battle would always be won by the strong, the wise would always find bread to eat, men with skill and understanding would always end up in wealth and favourable conditions.
Base your decisions on data, surely. But don't base them solely on data. Data only talks about what has happened in the past. Your decisions will affect the future. The future where time and chance have a significant part to play.