The relationship between healthcare worker fatigue and patient safety is among the best-evidenced findings in medical research. Numerous studies have demonstrated that doctors and nurses working excessively long shifts make significantly more clinical errors than rested colleagues — errors that can cause serious patient harm and, in the most serious cases, death. I strongly agree that legal limits on healthcare working hours are both justified and necessary. The fundamental argument is patient safety. A surgeon operating after twenty-four consecutive hours, or a nurse managing a ward on her fourth consecutive night shift, is functioning with cognitive impairment that research consistently likens to moderate alcohol intoxication in its effects on reaction time, decision-making, and vigilance. The patients under their care have not consented to being treated by a fatigued clinician, and the professional framework of medicine — which places patient welfare above all other considerations — is directly compromised by the culture of excessive hours that has historically characterised healthcare in many countries. Legal limits create an enforceable baseline that professional culture alone has demonstrably failed to establish. Critics argue that workforce shortages make hour limits operationally impossible — that restricting clinicians' hours would simply leave hospitals understaffed and patients without care. This concern reflects a real problem, but it is an argument for urgent workforce expansion rather than the perpetuation of a fatigue-based system that harms both patients and clinicians. Healthcare worker burnout, driven partly by unsustainable working conditions, is itself a major driver of the staffing shortages that critics invoke, creating a vicious cycle that limits alone will not break but must be part of addressing. Legal hour limits for healthcare workers, paired with serious investment in training and recruitment to address underlying staffing gaps, represent the only sustainable path toward a healthcare system that is safe for both those who work in it and those who depend on it.