doing a full service involves a pretty complicated disassembly, clean, and lubrication of parts. if the cd's are gripping and loading/unloading properly and the disks read. It's good. basically if it works, don't mess with it. a tiny bit of isopropanol alcohol on a cotton swab to gently clean the lens is really the only regular maintenance you need to do.
if you go crazy and start spraying moving parts with WD-40 to lube stuff up, it will work, but you end up attracting more dirt and gumming things up making a huge mess to clean up that can literally take HOURS.
most of the stuff runs unlubed to keep dirt buildup and grime down. very few parts actually require lubrication...and even then it's tiny tiny amounts.
resist the urge to get the compressor out and blow the hell out of the player...you'll end up with dust inside the laser assembly (not a sealed unit) and you'll have to replace it (it's not disassemblable.)