Stress is defined as "the adverse reaction people have to excessive pressures or other types of demand placed on them at work." It occurs when work pressures become too great and a person feels unable to cope. Stress is not an illness itself but prolonged excessive stress can lead to mental or physical illness. Work-related stress develops when the demands of a job exceed a person's ability to cope. It can cause sickness, absenteeism, and other issues. Whether a person feels stressed depends on factors like their skills, experience, health status, personality and personal circumstances. Signs of individual stress include emotional changes like mood swings or loss of motivation as well as mental symptoms like poor concentration. Signs of stress in a group include