There are limits to our ability to empathize. For one thing, empathy is exhausting, and we can deplete our empathy over time.
Like heavy-duty cognitive tasks, such as keeping multiple pieces of information in mind at once or avoiding distractions in a busy environment, empathy depletes our mental resources. So jobs that require constant empathy can lead to “compassion fatigue,” an acute inability to empathize that’s driven by stress, and burnout, a more gradual and chronic version of this phenomenon.
Health and human services professionals (doctors, nurses, social workers, corrections officers) are especially at risk, because empathy is central to their day-to-day jobs. In a study of hospice nurses, for example, the key predictors for compassion fatigue were psychological: anxiety, feelings of trauma, life demands, and what the researchers call excessive empathy, meaning the tendency to sacrifice one’s own needs for others’ (rather than simply “feeling” for people). Variables such as long hours and heavy caseloads also had an impact, but less than expected. And in a survey of Korean nurses, self-reported compassion fatigue strongly predicted their intentions to leave their jobs in the near future. Other studies of nurses show additional consequences of compassion fatigue, such as absenteeism and increased errors in administering medication. (Source)