May was injured when a forklift tipped over on her while she was moving stock in the company warehouse. Because of her injuries, she could not work for 3 weeks. Her employer paid her $400, which was half her normal wages for the three-week period. She also received $600 in workers' compensation for the injury. May is required to include the $400 she received from her employer in her gross income but excludes the $600 workers' compensation payment. Discuss why the payments are taxed differently.