American commanders in WWII were resigned to losing two Shermans for every Mark IV or Panther. The Sherman was undergunned and underarmored. The only Sherman that stood a one to one chance with a Mark IV or Panther was the upgunned British Firefly. The US Army had a tank able to take on the best in the Wehrmacht, the M26, with a 90 mm gun, but did not want to stop the Sherman assembly lines because they thought the war would be over by Fall of 1944. The Germans, meanwhile, brought out ever more powerful and complicated designs that were overwhelmed by the sheer numbers of Shermans, which were turned out like putty knives. In the end, the sheer numbers of putty knives won over technical superiority.