Hated to wear her bike helmet. Would always put it on the back of her head. One day, just after I had stopped her and had her put it on correctly, she took a spill, went over the handlebars and landed on the helmet. Never had a problem with her wearing it after that.

Same with some of the boys on my little league baseball team. They don't like the batting helmets and try to wear one that is way to large for them.