Doesn't matter how clean the car looks, they are always rusted under the damn mud flaps! There is literally only 2 visible rust spots on this car. A 1/4" spot under the rear window, and a scratch on the roof, but there are holes under all of the flaps. The rears have fist size holes! I can reach in and change the washer pump lol.

Part of the front ones are designed like it was intention to trap dirt and stuff.  I modified them and some of the metal to block / deflect and allow for draining better.