If the finish is oil and wax...
david weaver
...then I rewax.
If it's shellac and the finish takes a beating (I made a bookcase for my son when he was learning to stand, and he'd pull himself up on it and slobber all over the base moulding), then I try wax and if it doesn't work, refresh the shellac.
I've never gone beyond that on anything with lacquer other than guitars (in that case, buff, and if the issue is too deep, shellac stick and then buff.
Nothing stays perfect forever. The first few things I made, I really blasted with finish hoping they'd look like a mirror for years. Unfortunately, I didn't know that the items in question didn't really have that great of a design (they're still fine, still very few marks on them).
Since then, I like less finish thickness (more tasteful in most cases) and just give in to the issue of the pores telegraphing over time, even if they're not telegraphing after finishing whatever buff or rub out level you're shooting for.
I see a fair number of guitars that were made when the market started to turn and demand thinner nitro finishes vs. thick glossy encasements. I think that coincided with reading on the internet that such guitars don't sound that great. Some of the guitars that show their pores or other underlying wood movement the most are really finely made guitars by PRS and some other makers, but those guitars are just older, that's their only sin (by older, not old for furniture, but old by new electric guitar standards - like late 90s and early 2000s). Guitars made with a thick finish around the same time, of course, don't show any wood movement between the finish and give lots of room for error to buff out minor scratches, but I don't think they look as good.
A nice thing to do is stuff literature somewhere in the piece you're making stating what the original finish is. Maybe it'll never be found, and i"m not a furniture maker, so I don't know what standard practice is, but if I opened a drawer and a simple little piece of paper stating "finished with genuine lacquer" fell out, I would appreciate it just like I appreciate car manufacturers listing the fluid types near fill lids. I guess that's no longer standard practice in some cases, either.
