Their stuff has always sucked, they just make so much of it that numbers make up for quality. Even the famous T34 was quickly surpassed by the Tiger, TigerII, Panther, and even the later model MkIV. But the USSR built 50,000 T-34s, so they could afford to lose 5 tanks for every German one. Same ratio as the Sherman.
‘Quantity has it’s own quality’
Check the T-34’s weight against the Tiger’s or the Panther’s. Check which quality problems the nazi had at Stalingrad and what were the reasons of their tank losses.
Adding bolt on armor without adding HP is a bad mistake....
Many Panzer units removed the bolt on armor so the mk IV could actually climb a hill.
A Panzer leader once said that it took ten Shermans to kill one Panzer, but there was always an eleventh Sherman.