PDR is especially effective on smooth, shallow dents where the metal has flexed rather than folded sharply

https://sticky-wiki.win/index.php/Door_Ding_Repair_Made_Easy_with_Paintless_Dent_Repair

PDR is especially effective on smooth, shallow dents where the metal has flexed rather than folded sharply, allowing technicians to return the panel to its original contour.