The finish on the OP's gun doesn't look Factory to me.
I agree with The Kernel. I would consider advice from The Kernel nearly sine qua non when looking for information on "newer" S&W revolvers.
I am speculating from a cell phone with less than ideal picture size. It appears there's a large scratch on the side plate just above the trigger. It's pure speculation but it appears someone attempted to fix scratches on the side plate with an abrasive that was too aggressive and did the same thing on the left side of the frame to make it resemble the side plate.
The good news is this is easy and very inexpensive to make look much better. Regardless I would contact the seller to see what your remedies are. I and other S&W Forum members have posted how to "fix" scratches on S&W brushed stainless finishes.
Here is information I have previously posted:
You can touch up the original finish on a brushed finish stainless steel gun and fix significant scratches with Scotch Brite pads. You can make it look original and very nice.
Scotch Brite pads come in different levels of coarseness.
Light Grey, called Ultra Fine Hand Pad - (600-800) 800 grit.
Green, called Light Duty Hand Pad - (600) 600 grit
Maroon pad, called General Purpose Hand Pad - (320-400) - which is very coarse for removing deeper scratches.
Work in a small area with tiny (1" square) piece of pad and stroke in one direction only following the linear polishing direction from the factory. Avoid any surfaces but the brushed stainless surfaces. Start in the most unobtrusive area first to make sure you get a feel for it and like the result. Go slow and use a light hand. Generally the green pad can be used for all applications varying the pressure dependent upon the degree of the scratch you attempting to fix. You could finish off with the light grey pad. Look at You Tube for examples of how to do it or further research the S&W Forum.