https://en.wikipedia.org/wiki/AK-47#Concept
#1 "I was a soldier, and I created a machine gun for a soldier."
#2 "A lot of Russian Army soldiers ask me how one can become a constructor, and how new weaponry is designed. These are very difficult questions. Each designer seems to have his own paths, his own successes and failures. But one thing is clear: before attempting to create something new, it is vital to have a good appreciation of everything that already exists in this field. I myself have had many experiences confirming this to be so."
Particularly the latter could be a valid corollary to the Chesterton's Fence:
https://en.wikipedia.org/wiki/G._K._Chesterton#Chesterton's_...