"Don’t climb that high ..."

... don’t run so fast, or you’ll fall!’, ‘You are too little to do that’ or ‘Careful with that knife, don’t cut yourself!’ Overprotected children hear a lot of these phrases. But children want to practise, to get a chance to find out what they can do, so they can develop skills and body awareness. They need confidence in their own abilities to develop self-confidence. They do not want help with things they are capable of doing on their own.
We grown-ups would probably never have mastered climbing frames if people had kept pointing out to us the possible dangers involved. Skinned knees and bruises are a perfectly normal thing for an active child.