Two maintenance jobs matter on a refrigerator: the doors have to seal, and the heat the compressor removes has to leave the cabinet. Crumbs on the gasket and a refrigerator jammed into a too-tight alcove both show up as warm groceries and a compressor that never seems to rest.
You do not need to pull the whole box out on a weekly schedule. You do need to stop using the gasket as a napkin.
Warm air is the enemy
Close a dollar bill in the door. If it slides out with no drag along a stretch of gasket, that section is dirty, torn, or warped. Wipe with mild soap. A torn gasket is a part, not a wipe.
Vents inside and space outside
Keep the interior freezer vents visible — those slots in the back wall are how the fresh-food section gets cold on many layouts. Outside, leave the clearance the manual shows at the back and top. A cardboard “dust filter” stuffed behind the refrigerator is worse than dust.
Dust you can actually reach
Some models have a kickplate grille that hides condenser coils; others put the coils on the back. If you can see dust on an accessible grille, a vacuum brush on the grille is enough. Do not bend tubing or unscrew the compressor compartment cover to get a better shot.