One reason is that the result is intended for a machine, not a human being. Another is that the process is very different. The compiler assigns memory locations and registers in the central processing unit to instructions and data objects. It determines the precise order for directing computations in the CPU and the movement of data between the CPU and primary memory. It inserts instructions into the code to make use of routines already on the computer, for example, to compute a square root or display results on the screen.
Most compilers also optimize the object code in order to speed up processing.
Thus, any analogy between programming languages and human languages is extremely weak. Mathematical Function is Infinitely Expressible Software is not the same as speech about software. Programmers speak about their software all the time. They write descriptions and explanations of it, draw diagrams illustrating what it does, and prove properties about it. The mathematics of programming teaches us that the functionality represented in any given program can be expressed in an infinite number of ways.