It generally comes from someone else who acted as a caretaker when we were younger. We then take this on board and act it out even though the idea of being like that person may repulse us. Some real long therapy has helped me to shift away from this just a little bit and maybe over the coming years i can move further away.
When you act out perfectionism it usually comes in a form of criticising/judging/controlling and the recipient feels criticised/judged/controlled. Of course being good alcoholics we don't even need that other person to interact with as we find we can perform both of the roles by ourselves. it sucks for everybody involved and is extraordinarily damaging too.