So I was started reading a manga, Black Knight Story, which is set in the Eastern Front of WWII seemingly during the Dnieper–Carpathian Offensive when these two pages come up (read left to right rather than the usual right to left in manga):
http://i.imgur.com/l6MzhBS.png
http://i.imgur.com/SK4TKD4.png
Pretty much Panzer operator asked a mechanic why the T-34 seemed to have a slower firing rate compared to theirs. And then their officer and the mechanic both answered that the Soviets chose to use 4 man teams in their tanks (though apparently they began using 5 man teams?) and that they chose to focus on a different shape for better armor.
But its not just this, from what I know I heard the Italians also used mainly riveted armor in their tanks (which from what I understand was bad as when hit, the bolts would sometimes shoot right into the tank and perhaps kill the crew, whether this is a myth or not, I don't know).
So yeah, I am curious on what were some of the design choices between each country and why did they choose them (whether out of cost, lack of technology, etc)?
The use of tanks varied greatly among different nations during WWII. An example of this is the German Panzer Division, compared to the Japanese tank divisions, most of which would be unknown to you.
Tanks were pretty new, only invented during WWI, and were generally not worth it. The evolution from then to WWII, and even today, is massive.
Choices between tanks varied between countries. Germany used the famous "Blitzkreig" tactics, which relied on speed, planning, and surprise over anything else. For this reason, they would have designed faster tanks, but also relatively strong to shoot back any resistance.
The French tanks, on the other hand, were slower, and almost 80% of them lacked radios. The French had thought the combat would have been the slower paced type, from WWI, which is why they were so devastated, and didn't have time to defend their country by the time they were surrounded.
A general trend was heavier tanks and, by 1939, most tanks had an armour of 30mm or less, with guns around 37-47 caliber. By 1945, the average tank had maximum armour over 60mm, and guns in the area of 75-85 caliber. It was the start of the differentiation of light, medium, and heavy tanks. Light tanks, which had dominated the playing field earlier in the war were gradually withdrawn from service.
Turrets were not loved, but still considered very important. If a tank was to engage armoured and infantry units, it could have to have a powerful gun. One which could only be supported by a stronger turret. Hull-mounted guns were installed, but meant that the tank would be exposed to enemy fire. In return, however, it would be able to give "hull down" cover, and protect from infantry at short range.
All in all, tanks had different jobs, and each nation had a different plan for each one. For example, the Panzerjäger, a German which carried out it's name, the "tank hunter". It was pretty much an anti tank gun on a chassis.
The famous Soviet T-34 tank was based on this idea, like the Panzerjäger, that an older and lighter chassis to mount assault guns or larger weapons. For example, while the T-34 would normally hold an 85mm gun in the turret, the same chassis could hold an 100mm gun. This could be used to make lighter, but stronger tanks, but normally in sacrifice of some armour. The German Panzer III (And later versions) were unique in that they had better armour than their counterparts
In conclusion, nations using different shells, crews, and tactics makes this question much broader than you may think. More crew was more efficient, but tanks were VERY uncomfortable and you wouldn't want it more cramped, less you lose performance. Many myths may be true, or just a way to improve the morale of the soldiers who were attacking these "weak" tanks
I hope this helped!
