yeah but there is 2 metal plates on the inside of the car when i take a door off a vehicle i put these back on the door as they are needed to hold door on and when a doors are removed people sometimes drop into the shell etc

they are around 10mm thick so if they was left on the outside between the hindge and the car it would explain the gap if yours was used inside the car as normal then it would explain why the door was held inplace just a thought

(easy mistake) although i did notice before i fitted it just lol