From the NYtimes:

"In 2000, the British psychologist James Reason wrote that medical systems are stacked like slices of Swiss cheese; there are holes in each system, but they don’t usually overlap. An exhausted intern writes the wrong dose of a drug, but an alert pharmacist or nurse catches the mistake. Every now and then, however, all the holes align, leading to a patient’s death or injury."

We have to fix the systems.

References:

The Phantom Menace of Sleep Deprived Doctors. NYTimes, 2011.
Image source: OpenClipArt.org, public domain.

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