Once, about three months ago, I permitted a forbidden soft drink. I have learned that, for this particular child, being consistent does mean doing exactly the same thing every time, because it frees him from the necessity of trying to win an argument. It gets us out of the power struggle loop and allows my son to focus his energy on more productive things. There is no question that parenting a child like this requires more mental energy. If parents give the first response that comes into their heads, they may pay for it later.
Children plan their strategies carefully, too.
They learn early that if mother is sewing or on the telephone, she is more likely to make quick decisions about snacks or bikes in the road. My son knows that I mean it, because I follow through every single time. This kind of approach to discipline is obviously not necessary with every child. Children like my daughter need a lot of freedom and space to soar. Others, like my son, need more structure to set them free.