Not proper English I know, but you get the point, especially it you ever had a parent frustrated enough with the "why?' to say it.
Somewhere along the line in our modern day of intelligence some genius decided to teach that parents needed to first sit down with 'little Johnny or Susie' and explain the consequences of his or her decisions and affect on others in matters of discipline.
Wonderful, Johnny or Susie runs out into the middle of a busy street and you need to first explain to them that this is not a good decision and perhaps could be detrimental to their health and stressful on others driving that way today. Brilliant!
What the kid needs to have screamed at them is, "Come here, NOW!" And if they live long enough to ask the obvious, "Why?"; the answer should be, "Because I said so!"
The beginning of man's fall was questioning God's authority and word. That hasn't changed for thousands of years. To this day man is still asking, 'why?'. The answer is, "Cause God said so". You don't have to understand all the whys, and in reality in this life, you never will. There are indeed consequences to our actions and we live them daily. But, until you are willing to learn by reason, you need to know to act because God said so.
Parents are to example God's ways, not the ignorance of society in the home. You are not your child's friend when they are too small to understand. But, your voice is the first thing they relate to. They need and even desire the stability of consistent tone in your voice in acceptance and discipline. They need to know the reality and consequence of "Cause I said so!" Nuff said.