Positive reinforcement

What is the use? Or is there a use?

As studies have shown positive reinforcement is, like praise, rewards and other stuff like that an external motivator and with that not giving the child much intrinsic motivation, which is in general the best motivator a person can have. Intrinsic motivation will keep a person doing what they do (learning) and trying to become better at it. When there is praise, grades or whatever used, the child will work for the praise, grade or whatever, but not for the fun of it learning. What you can see is when a child is interested in something they will keep at it and learn more and just dig into it.
When a child is getting praise, they will not go for the topic, but for the praise and with that the topic becomes uninteresting.
Children love please their parents and teachers, therefore they will do what is necessary to please them, i.e. get a good grade, but do they remember anything from what they learned afterwards?
I do remember getting great grades for things, but don't remember much of what I learned in school in order to get those grades. I do remember being totally fascinated about a topic, which was not taught in school, so I went to the library and dug and dug, I was 12 and still remember the photographs.
Okay, I know.... this sounds like only unschooling is good. I wont say that, coz some kids love it in school so there is no need to meddle with that. But make sure that the children know that its not about the grades, that you as a parent are not interested in the grades, but in what they learned. You can do that by ignoring good and bad grades, but asking about what they learned and what they liked about it and all that stuff. Just by showing interest.

And this goes for other parts of parenting as well. Why would it be a good job if yr child makes a drawing, its not necessarily a good job. It can also be a crappy scribble job, but there is no need to say good or bad. Just say that you see scribbles in red and blue. Ask about the feelings or motivation that made your child make that drawing.

When I go to the playground I heard a load of "Well done" 's all the time for nothing.
When a child goes into a playground, what is the use in saying "Well done" when they go on the swing and swing. Isn't that normal for a child to want to do and have fun?
Or climb into a climbing rack? Isn't that just fun and stuff?