Why didn't China, the ancestor of mechanical clock, develop it?

Your question is very interesting.

The reason is that in order not to delay the farming season, the agricultural society has determined 24 solar terms, which has no realistic motivation for the time change of a day. The pace of life of ancient people was very slow.

In medieval Europe, it was mainly for religious reasons. Among many Christian sects, Benedictine is the most orthodox and respected. Medieval Christians, especially devout Christians, prayed four times a day. On average, there are four hours in 24 hours. It can't be early or late. At that time, devout Christians believed that no matter you were a pope, a king or a beggar, as long as you prayed once, you didn't do it.

That's when the name "night watchman" came from. The night watchman's job is to stare at the clock and wake everyone up at midnight (or early morning) to pray. This position is very responsible! If a night watchman neglects (possessed by the devil) and fails to wake everyone to pray, it will put other devout Christians in a hopeless situation! Medieval towns were built around churches. It is the duty of Christians to listen to the morning prayers, noon prayers, evening prayers and midnight prayers of the church regularly to complete their prayers.

So the church must have a timer.

After 1700, the watchmaking industry improved, and many businessmen can buy a big clock at home. I can proudly announce that I also have the "time" given by God. Pocket watches have also become popular, but they are very expensive. At present, the first pocket watch recorded in history is a pocket watch made by a watchmaker, Mr. Breguet. He ordered it from Switzerland and gave it to his queen.

The popularization and spread of Christianity in Europe is an important driving force for the development of watch industry.