I have noticed that in various wars, that weapons are produced based on various ideas and theories but that due to various factors in the war, that cannot be foreseen, that in fact, changes are made to vehicles and things develop in ways that were NEVER FORSEEN – not could they be foreseen.

The Panzer IV is such a case. It was a "Support tank for tanks". It had a short barrel and was to be used to do things other tanks could not. However, due to the changing nature of the war, they put a longer gun on it and turned it into a tank that fights tanks. This amazing vehicle was modified endlessly and fought from the beginning of the war to the end.

This rather boring tank made up about 30% of all tanks produced by the Germans during WW2.

This is the story of this rather boring, but amazing vehicle that served Germany incredibly well:

https://www.youtube.com/watch?v=1LWes0vD_no