Praise intelligence -> makes them give up easier. Praise hard work -> could be a subtle attempt at manipulation. Maybe instead we should ask them what they want to do, and support their creative activities.
What a child wants to do is what a child wants to do right now . If you ask the same question a few minutes later, you could get an entirely different answer. As adults who have lived through being children, a surprising percentage of us actually do know better than a small child what's best for the small child for a surprising percentage of their lives.
I wrote from this point of view, but I agree that parents and teachers know better most of the time, I just don't know if it is good to try so hard to make sure the child doesn't make any "wrong" choices.