Japan has learned to take burnout seriously. Companies, schools, hospitals and other organizations increasingly recognize the dangers of excessive workloads, long hours, chronic stress and deteriorating mental health.

But another workplace problem receives far less attention: “rustout,” the distress that can arise when people’s abilities are persistently underused. The term is not a medical diagnosis. It describes familiar problems such as boredom, disengagement, underload and a loss of meaning when people have too little challenge, autonomy or opportunity to contribute.

If Japanese organizations are serious about preventing burnout, they should also ask whether some employees are rusting out.