At the start of Barbarossa the Germans were unaware of the Soviets’ T-34 and KV tanks each of which could destroy their best tanks. The KV’s armor was impenetrable with German 5 cm guns except for close range side and rear shots.
The Tiger I began as a breakthrough assault tank project in 1937 whereas the Panther and up-gunned Pz IVG were responses to the T34 and KVs.
The biggest mistake IMO was shelving development of the 7.5 cm Pak 40 from ‘39 - ‘41.
“At the start of Barbarossa the Germans were unaware ...”
Was it arrogance or InTel failure? I know the Germans were spying on us and England.
“The biggest mistake IMO was shelving development of the 7.5 cm Pak 40 from 39 - 41.”
Germany was using jet engines in the 30’s but Hitler thought they wouldn’t work.