I never tried polishing them. Some of the newer ones have a much rougher cooking surface than the vintage ones. But some of the more expensive modern ones are polished at the factory. But as long as they're relatively smooth to start, it's the repeated seasoning, and everyday use with oils and fats over time that will eventually make them nearly non-stick. Removing it all down to bare metal, as I just did, means I have to start that over again. But that's ok. I like to cook.... and eat.
I get on an iron kick sometimes and cook a lot with them for a while. I have several Dutch ovens too. The skillet I'm working on now is an old Wagner #10.