I clean my guns after every time shooting.
I typically run some wet nylon brushes of hoppes and then mop up the rest of the powder fouling with some patches. I notice that my bigger bore guns tend to get dirtier than my smaller bore guns.
On new barrels, I shoot at least 50 jacketed rounds before going to cast. I don't do the whole shoot one, clean, shoot three, clean etc. But I do run some sweets through if I get any blue indicator from the hoppes. If I end up using sweets, I clean the barrel squeaky clean.
But my buddy bought an AK years back and he is specifically is NOT cleaning it. He claims that it's an experiment. I think he just doesn't like to clean guns. I have another buddy that never cleans his guns and one of them used to shoot dead on, but shoots like **** now.