Encouraging careful behavior by increasing risk

The Wife’s work has brought her into contact with people involved in digitizing ancient (and precious) unique manuscripts. They were handling the manuscripts only while wearing cotton gloves, but the gloves have been ditched. The problem with the gloves is that people felt that wearing the gloves automatically protected the manuscripts, so they became careless—and moreover, with the gloves on they lost tactile sensitivity and could not readily tell how gently/roughly they were handling the manuscript.

That reminded me immediately of a German traffic control discovery: in urban areas and city centers, if you make the separation of automobile and pedestrian traffic unclear—e.g., by having a large open space open to both cars and people—it makes both  drivers and pedestrians much more careful, with the result that the frequency of accidents drops sharply.