Two problems the Britisgh faced, one was non standerdisation. The Subsidy scheme bettween the wars allowed vehicle users to purchase a a unit with a subsidy provided it was made available for military use. This was a motor version of the original horse breeding scheme. There were a lot of manufacturers all producing vehicles that coomplied with the scheme. The result was the most mechanised army in the world, just a multiple supply chain. The US on the other hand only had about 21, 00 vehicles in it's entire armed forces. Following the faluire of the Liberty Truck in the Great War, a typical miltary Camel, a horse designed by comitte, the USQM Dept. issued requirments, one of which was that the vehicle had to conatin as many standard parts as possible. The result we all know, and many own, one type but made to a master blueprint, regardless of actual manufactuer. As the US relied much more hevily on long distance heravy trucks, than Uk, that used the rail network, US designers had more experience of designing reliable heavy vehicles. There was also a diffrent ethos of production. In Britian , an apprentice served five years or more and could build a vehicle from the metal ore to finished vehicle. In US the Ford model production line was a person trained to do one job, and did only that job.
The end result was large production of standard vehicles with a lot of interchanagble parts, hennce short supply lines. Also US was not subject to the blitx etc so production was not disturbed.
As for the Russiansds, they have never been backward at stealing others designs, also they has a lot of input from Ford in their early production, so used the Ford methods. The best Tanks during the war were probably Skoda, and of course used by the Germans after the factories were captured.