I believe every carry gun should always be cleaned after shooting, range session etc. It allows you to check for any damage, excessive wear, or brass shavings that may have been left behind. Once every two weeks I clear the mag and chamber and run a dry toothbrush through the magwell breechface, chamber etc. with the slide locked back.
M&P's, Glocks, etc. have a lot of clearance between the slide and frame, and at the rear of the slide for dirt, lint, and dust to fall into the inside of the trigger/sear and moving parts area. This is a another reason to use "minimal" lube. Grease and heavy oil will cause debris, fuzz from clothing, and dust to stick. I use a little more lube than what the manual recommends, and after 30 years of using all kinds of "wonder oils" I just use synthentic motor oil now, but use whatever you like as long as it's slippery and doesn't evaporate like w-d 40.
I use bore solvent in the bore, let it soak, brush, patch, then spray plain old cheap carb cleaner through it. Dry patch again, then light oil patch and wipe down with oil on a clean rag. If you can, have a little workbench with a bright light and always visually inspect the moving parts. You don't even have to know what you are looking at, but with common sense, you should be able to tell a peice of organic matter, lint, brass shavings or a part that does not look right. Look for hairline cracks and gouging on steel parts, pins not lined up, and polymer damage/wear.
Reassemble, then rack slide a few times and dry fire a dozen times or so, make sure everything FEELS right, and you will FEEL confident carrying a clean and visually inspected pistol that you checked yourself.
