There is another point to think about. SJS’s approach which seeks to make all the rules understood to the child, is very noble. However, the implication is that if the child does not understand the rules, or does not agree with the rules, then he is free to conduct himself otherwise. In other words, the child and Mommy are on the same level of authority. This is precisely what may spoil a child.
In addition, there are many situations where Mommy simply cannot explain things at that moment. What is needed is immediate compliance. For example, Mommy is on a telephone interview about an important job, and the child wants to take all the cookies out of the jar. Mommy says no, and the child won’t listen or is threatening a tantrum. Is Mommy going to tell the prospective boss to hold on, and then proceed give a long lecture to the child on why too many calories is not good for health, and each cookie has about 25 calories, so it is not advisable to eat so many now?
The point of a potch is that when Mommy or Abba says NO, it means NO, right now, no negotiations, no discussion, no disobediance. Later on, you can spend as long as you want discussing nutrition with your child.
A potch or two early on hopefully will guaranteee that from then on, the child will understand the word no, and potches will not be necessary. A child must learn immediate obediance to authority.