Even after writing about watches for a good five or six years, I have only a slightly-better-than-average understanding of how a mechanical watch works. Explaining the difference between quartz and mechanical movements is simple enough. The former uses electronics and a quartz crystal to keep time while the latter uses a series of mechanical parts to achieve the same results. But how exactly do all the parts function together to create a machine that can quite accurately keep time? that is the part that is hard to explain.
The way I usually explain it is that a mechanical watch uses a wound spring for power, and has a regulating organ that, well regulates, the release of said power and through a series of gears and wheels, it is displayed with hands that track the hour, minute and second. It’s quite vague for sure, but that was the best verbal description I could come up with. Thankfully, I have just stumbled across this video online that explains the basic principle of a mechanical watch perfectly and has an animation that will help everyone visualise the concept much better than my words ever could. Enjoy.