In an emergency situation you react. I would probably grab my dog by his harness/toddler by the hood of their jacket if they were about run into a road (my dogs and kids were NEVER near a road unrestrained for that to actually happen)
In a teaching/training situation which would be more effective?
I am teaching you how to do something, I speak a foreign language, everytime you make an attempt at what you think I want, I growl 'NO', and poke you in the arm.
You try again and get the same reaction. This goes on and on until you feel the bruise starting to develop and it hurts.
In the end you give up trying to do anything because you worry that you will get it wrong and will get poked again. It is far safer to not try anything and to just sit still and do nothing, you haven't learned anything but at least I am not poking you anymore.
Or
Same situation. But I sit and wait, you try various things and get no reaction. I make encouraging noises and smile because I want you to succeed and achieve what I am trying to teach you.
You keep trying, I am still smiling and encouraging you, you reach up and touch you earlobe, I say a cheery 'Yesss!' And pop a cube of chocolate in your mouth.
You try and remember what you did that earned you the chocolate. Again you try a few things, you tap your knee, you wiggle your foot, then you remember, you reach up and touch your earlobe, I say, 'yesss' and give you more chocolate.
This time you know what you did, you go straight for your earlobe, I say, Yessss, you get the rest of the bar of chocolate. We end the training session and the next time you come in you remember what you did to get the chocolate and offer the behaviour straight away.
In which way did you learn better?