factories use shift work if they have to operate for extended hours. it works well only if the jobs are repetitive from one shift to another.
hospitals operate 24 hours a day & nurses go on shifts as well. however, the work here is not repetitive, so this system will not be as successful as in factories.
so, if a nurse fails to do a task in the morning, the probability is high that the afternoon shift nurse will overlook the task, & even if she discovers the shortfall, she may choose to disregard it, esp. if the pervading attitude is lackadaisical.
that's why i just gave the afternoon shift nurse a mouthful, because the patient's condition is critical & any shortcoming can be lethal.
now, imagine, the 1st line doctors in public hospitals, the housemen, are working shifts. if you extrapolate what happens in nursing, you can imagine the consequences.
shift work for doctors is
ok, i confess, i don't know what it's really like in the dark ages but you get my drift.