Ultimately, Deming’s line is a call for disciplined judgment, not data worship. Bayesian thinking—updating beliefs as evidence arrives—captures the spirit: models and priors inform experiments, and results revise the plan. As George Box and Norman Draper noted, “All models are wrong, but some are useful” (Empirical Model-Building and Response Surfaces, 1987). Thus, the wise leader demands data, pairs it with theory, and maintains humility about uncertainty. In that balanced posture, trust is earned: not by faith in numbers, but by a repeatable process that learns. [...]
