How well you maintain any gun, determines how long it will last.
If you don't care about keeping it in good condition, or you're independently wealthy and can afford to just pitch a gun and go out and buy a new one when one rusts, don't bother cleaning it.
Personally, I'm not wealthy, and I pay for my own guns so I take good care of mine.
I clean it EVERY TIME I shoot it.
A good maintenance method for a pump gun is:
Use a rod and bronze brush to brush the bore with solvent, then run two patches soaked with solvent down the bore.
Allow to soak while you clean the rest of the gun.
SOAKING is what does the major cleaning. The solvent needs time to work.
Use solvent and a special chamber brush to clean plastic and powder fouling from the chamber.
Chambers are bad about rusting when used with plastic shells, and sticky, fouled chambers cause most extraction problems.
Use paper towel and toothbrushes to clean fouling and plastic, brass or steel shell particles, and burned powder particles out of the action and bolt.
Every once in a while clean and inspect the magazine tube.
Dry and re-lube the action.
Wipe the bore and chamber with dry patches, inspect, then apply a thin coat of rust proofing lube.
Use a toothbrush to apply a thin coat of rust proofing lube to the entire gun.
While it's down, inspect the entire gun for wear, corrosion, broken or cracked parts, weak springs, damaged or worn extractor, ejector and firing pin.
Many of my guns have been heavily used but other than some finish wear look and are like new.