We delete pictures that gets reported if the advertiser can't prove that he has licence for the thumb used and can't prove that the person in the thumbnail is of legal age.
Some thumbs that have been reported for looking too young has been proven to be legal and licenced. In such cases we have not deleted what has been reported.
Even if they 'just' look too young. I don't want those images on my site and tbh it turns me off of any site I see them on.