When you buy a cheap watch from a store, you expect to use it for a few years, maybe replace a battery once or twice, and then get another watch once the first one wears out. However, if you're about to buy a high-quality, mechanical watch (not a digital one or an analog quartz one that works with a battery), this is not a timepiece that you want to neglect. These are traditional watches that have to be wound and checked. They can look fantastic and function well as long as you care for them properly. These watches should be serviced every few years to ensure they keep working well for a very long time. Servicing includes checking and repairing some basic but necessary features of the watch.
Check and Repair Water Resistance
Many watches claim water resistance now, with some able to handle the pressures of diving. The water resistance relies on gaskets that keep the interior of the watch sealed up. These gaskets, as with any gaskets, can wear out and dry out over time, creating small gaps that let moisture into the inner workings of the watch. During servicing the watch repair person can replace worn gaskets and inspect the other gaskets (sometimes even replacing all of them just to be sure they didn't miss any small problems). If there are signs that moisture has intruded into the interior of the watch, the repair person can inspect the parts and repair those that may have been affected.
Lubrication and Repair of Worn Parts
Mechanical watch parts have to be lubricated; otherwise, the friction created as the parts move could make them wear down prematurely. The lubrication oil inside watches can dry up as the watch gets older, and new oil needs to be added. During servicing, the repair person will check the internal parts for wear and add enough oil to keep everything running smoothly.
Cleaning, Demagnetization, and Cosmetic Fixes
Also a part of servicing are general cleaning and polishing, demagnetization, and other cosmetic fixes. Demagnetization can actually be done at home, but if you're taking the watch in to have work done on it, you may as well have the demagnetization done there. Magnetization can make the watch run faster, so it is almost constantly ahead of the correct time. Scratches, smudged faces, and other cosmetic issues can be cleaned up so that the watch looks almost new.
Regular servicing prevents a lot of problems from happening and also allows for repair of those small problems that were starting to form unnoticed. These minor repairs can help you avoid major problems.