What was Leonardo DA Vince's worst and best invention he made?

Leonardo da vinci's best invention is often considered to be the flying machine, as it showcased his visionary understanding of aerodynamics and inspired future developments in aviation. Conversely, his worst invention might be the armored vehicle, or "tank," which, while innovative, was impractical with the technology of his time and never saw practical use. Both inventions reflect his genius and imagination, but also the limitations of the era's engineering capabilities.