According to Quantum Mechanic and No-cloning theorem perfect cloning is not possible. The key thing is superposition. Even if we know everything about the parts of the system, we don’t have the full knowledge about the full system. We can simply visualize that with the simple math operation:

$(A + B)^2 = A^2 +2AB +B^2$

is not the $A^2 + B^2$. It is not enough to look only at the parts of the system and try to apply the same operation as on the full system.

MinutePhysics