My father retired at 65 last year, and within six months he'd started a small woodworking business from his garage. Meanwhile, a colleague at my firm was forced out at 70 despite still mentoring half the junior staff. We treat mandatory retirement as a fairness mechanism to open jobs for younger people, but in a knowledge economy where experience compounds, isn't forcing someone out based on age just a form of waste? If a person is healthy and productive, why should their birthday dictate their career's end?