During cellular respiration in both mitochondria and aerobic prokaryotes, the Electron Transport Chain pumps H⁺ ions out of the matrix or cytoplasm to create a H⁺ concentration gradient. This forces the H⁺ ions back into the matrix or cytoplasm forcing ATP synthase into action. Why are the H⁺ ions pumped out of the matrix or cytoplasm, instead of into it? For aerobic prokaryotes, and the early mitochondria (which were prokaryotes living on their own) pumping the H⁺ ions out of the matrix or cytoplasm means pumping them into the outside world, a very uncontrolled environment. There is nothing to prevent the H⁺ ions from diffusing out, making the pumping completely inefficient, if not pointless. Wouldn't it make more sense to pump the H⁺ ions into the matrix or cytoplasm, where the H⁺ ions cannot diffuse, resulting in much higher efficiency?