What ever shape the object striking the panel is, can transfer itself onto the car body panel. Many outward shapes are also formed when the panel has been forced against impact bars in doors for example.
Inner strengtheners in tailgates can leave very nasty high spots, often splitting the paint.
A Paintless Dent Repair Technicians role is to carefully examine the damage prior to any repair taking place. It is vitally important before working the metal to determine the nature of the dent.
Starting any dent repair incorrectly could very easily jeopardize the final outcome
The strength of the car body panel will also determine the shape of a dent.
Certain makes of vehicle use a finer grade steel for the production of the panels, leading to excess stretching of the metal when the panel is struck.
Dents/ dings in light weight panels can sometimes be extremely difficult, if not impossible to repair.
Dent removal from an over stretched flimsy panel would be like trying to repair a sheet of polythene.