1) A lack of physical or mental abilities that results in a person's inability to manage his or her own personal care, property, or finances. 2) A lack of ability to understand one's actions when making a will or other legal document. 3) The inability of an injured worker to perform his or her job. This may qualify the worker for disability benefits or workers' compensation. 4) Under the Family Medical Leave Act (FMLA), the inability to work, attend school, or perform other regular daily activities due to a serious health condition, treatment for the condition, or recovery from the condition.