It offers the opportunity to develop a working rhythm and test one's stamina. Volunteering is another route back into the mainstream. The loss of benefits or the fear of losing them may keep some people from seeking employment who might otherwise jump at a job opportunity. While the impact varies depending on the specific benefit, the simple fact is that most people will be better off financially by working. True, they will lose some benefits, but for public benefits at least, their work incentives are sufficiently attractive to encourage employment.
Private benefits are a different story.
The continuation of some private benefits is contingent upon the inability to work. A private benefit recipient who works could lose those benefits, and the hope of ever regaining them. A decision to return to work is rarely considered without reference to a specific job or career field. An impaired immune system is a good reason to stay away from things, jobs included, that are unpleasant. If they have been unemployed for long periods and have adapted financially and professionally to long-term unemployment, they can frequently make informed choices about jobs based on personal interest and not on financial need.