Steel wool will imbed itself in the surface of the stainless steel it's being used on.
Howdy
That is correct. Stainless steel is a steel alloy with a certain percentage of chromium in the alloy. The reason it is 'stainless' or corrosion resistant, which is the actual term, is because the raw steel forms an invisible layer of chromium oxide (passivation). The layer of oxide forms naturally with exposure to the oxygen in the air. The oxide layer is colorless, and does not alter the appearance of the steel. But like all oxides formed on the surface of steel, it prevents atmospheric oxygen from reaching the body of the steel, so it protects from further oxidation.
(Gun blue is another type of rust or oxidation. It prevents atmospheric oxygen from reaching the body of the steel.)
The chromium oxide that forms on the surface of stainless steel is a natural process. Scratch the surface, and the layer will form again, still preventing corrosion.
If regular steel wool is used on Stainless steel, chances are small particles of the steel wool will embed themselves in the surface. This can defeat the passivation layer. If the particles of steel wool start to corrode (rust) the corrosion can then get past the passivation layer and begin to corrode the body of the Stainless steel.
P.S. There are many different alloys of Stainless steel. Some have more chromium in them than others. Generally speaking, the more chromium in the alloy, the more corrosion resistant it is. The flip side is increased chromium content can make the steel more difficult to machine.
I bought a cheap set of stainless steak knives a few years ago on the internet. They are 'stainless steel' but everyone of them has developed spots of corrosion. Not very good Stainless steel, probably why they were cheap. I have stainless revolvers I have shot lots of rounds of Black Powder through. Some of them have developed some spots of corrosion, some have not. Different alloys.