Origin of Movements
Most mechanical movements today are made in Switzerland, Japan or China.
Swiss. Although Swiss movements are popularly considered to be at the helm, Swiss watch regulation only requires just 51% of the component value in a movement to be made in Switzerland in order to be labeled “Swiss”. This area of the regulation has been misinterpreted, allowing many movements to pas as “Swiss” despite having many parts made in other parts of the world.
Japan. Many, if not all of the major Japanese movement manufacturers have a very long history of innovation and with renowned, exacting attention to detail. It can be said that Japanese movements are considered by many to be equal, and in some cases, better than Swiss movements. In comparison to the Swiss made watches, many people believe the Japanese movements offer a possibly superior level of quality to Swiss movements, but at a lower price.
China. The “Made in China” label has the unfortunate connotations to mean cheap, and low in quality. Perhaps, that may be true for mainstream general merchandise. However, China does have a very long tradition of watchmaking that going back for decades. The largest watch movement maker in China, Tianjin Sea-gull is still the largest movement manufacturer in the world today. While it is true that quality among mechanical movements made in China varies widely, some effort spent on research into their manufacturers before purchase could go a long way to protect yourself from buying an unreliable watch.
Even though mechanical movements are less accurate than quartz, they are still very accurate and reliable.
A decent mechanical movement is accurate to -20/+40 seconds per day. This means that in a 24-hour period, the watch may be 20 seconds slower to 40 seconds faster. But factoring in the fact that we have 86,400 seconds in a day, it works out to a very high 99.95% accuracy. The more expensive and higher end mechanical movements which are rated for even greater accuracy, have an accuracy of only a few seconds per day.
Many manufacturers are conservative in their accuracy claims, and many mechanical movements run better than the manufacturer’s specification, without any further adjustment or regulation. It is common to find to your pleasant surprise that a movement rated as -10/+30 or -20/+40, will only gain or lose a few seconds per day, in contrast to the specified accuracy.
Power reserve refers to how long a watch will run when it is fully wound up. Most mechanical movements have power reserves of about 40 hour. More expensive watch models have movements with power reserves lasting many days.
The Things That Matter
In mechanical movements, beat rate, accuracy and power reserve affect reliability. Increasing or improving one aspect can restrict the performance in other aspects. It is a fine balance of technical skill, that requires the watchmaker to make adjustments, or implement some other measure to compensate for the weakened functionality in an area. In any case, a mechanical movement will be designed to achieve an optimal balance of beat rate, accuracy, power reserve and reliability.
A mechanical timepiece is a piece of engineering beauty that deserves to be appreciated.