The COVID-19 pandemic highlighted, sometimes painfully, the stakes of decision-making in a context of significant uncertainty. Social distance, wearing a mask, confinement… difficult choices with significant health, social and economic impacts. To guide and justify our decisions, the principles of precaution and prevention have been used. Invoked like mantras to protect us from bad luck, are these two principles really a panacea for these situations ? Not sure… Beyond their intrinsic moral value and the rationality they bring to the decision-making process, their implementation suffers from serious limitations. Doesn't their use make us forget the essential ? The need to tackle the roots of the problem before ending up in an uncomfortable toss-up.