https://tanks-encyclopedia.com/ww1-germany-treffas-wagen/

The engineers of Hansa-Lloyd, having no experience with designing either armed or armored vehicles, came up with a big-wheel design which they called Treffas-Wagen. A single prototype was completed on February 1, 1917.

When the vehicle was subjected to thorough tests in February and March of 1917, many fundamental problems were encountered. The guns had such a powerful recoil that, after firing just a few shots, the gunner could not continue shooting due to significant head and shoulder pains, which raised grave concerns over the vehicles operational ability. Another issue was the center of gravity which was too far forward. When driving over a ditch, there was a high chance the vehicle would flip itself, which actually happened during a test in the summer of 1917. The vehicle dug itself in, got stuck, and eventually flipped itself over.

All issues combined, this vehicle had serious engineering problems caused by the design, which is not so strange given that this vehicle was one of the first of its type and the first armored vehicle designed by Hansa-Lloyd. On May 14, 1917, a demonstration was held which included the Sturmpanzerwagen A7V wooden mock-up, the Orion-Wagen, the Dür-Wagen, and the Treffas-Wagen. After these trials, the OHL (Oberste Heeres Leitung – Supreme Army Command) concluded that the Treffas was unfit for combat use and rejected the design.