>>938973187
A paper airplane has 1 function and anyone who understands newtonian physics can figure that function out. An origami crane has numerous functions, some logical but most are intangible. They perform aesthetic functions.
Designing a paper airplane while knowing the objective is easy. Designing an origami animal is harder not only because the function is aesthetic, but because the objective itself is not presented as a simple physics problem of an object with lift coefficient on a ballistic trajectory. The number of factors left up to intuition increases exponentially. Creativity or intuition allows you to navigate these decisions, not logic.