Every 4 to 5 years would be good for servicing a mechanical watch, in your case with the extra mention of regulation.
A mechanical chrono is a terrifyingly complex device that needs pampering.to keep it at the top performance.
This service might be expensive, but still I would only order it from an authorised dealer.
Anyway, as I wrote elsewhere, 1 minute per month is an error of 1/(60*24*30) or only 0.02% (!!!), which in my opinion is very acceptable for a mechanical device.
Hence, I expect that it is within spec.You cannot expect the same accuracy as with a quartz watch.

People like thos "crappy" mechanical watches for far different reasons. For me it is not an "A or B" question, I can see myself alternatively wearing a mechanical wathc or an iwatch, depending on the occasion.

Fair enough, you are not in the market for a mechanical watch. If you'd buy a mechanical Grand Seiko or (usually) Rolex etc, then you could perhaps (!) reduce this to 20-30 seconds per month. Considering that this is all traditional mechanics, that would be as flawless and high a standard as you can get. Even 1 minute is an error of 1/(60*24*30), in my opinion a good result.
If you can't live with that, then quartz or atomic is the way to go. Nothing wrong with quartz, and in my opinion there is also nothing wrong with loving the intricate mechanics of traditional watchmaking, at the price of applying small adjustments from time to time.

For precision, buy any $20 quartz watch. A mechanical watch is for those who love the beauty of the pure mechanical engineering. Some watch aficionados are snobs, some are not. I have as mall collection of watches, none really expensive, half quartz, half mechanical. I like m mechanical as much as I like my quartz in different ways. 1 minute per month is a few seconds per day, something I can easily live with and fascinating from an engineering point of view.

Come on. It is still good, and falls within the COSC guidelines of something like +-4 seconds per day (sorry I forgot the exact deviation). For a mechanical construct, this is still well done. And what is wrong with liking the beauty of mechanics? For precision any $20 digital watch will beat all mechanical watches.

This Tag Heuer of the parent is an automatic, mechanical watch. Think about it, one minute accuracy over a month realised with only vibrating springs etc. That is technically impressive. FYI many quarts watches are rated +- 15 seconds per month, only 4 times better!
Nothing wrong with enjoying a mechanical watch for the joy of the fine engineering, and the pleasure of the nearly smooth second hand.
Interestingly, the mechanism of the modern Tag chronograpths is a close brother of a certain Seiko movement, something that the Swiis company prefers not to mention.

In fact the inflation of Rolex in recent years is such that you may well be able to sell a Rolex you bought say 5 years ago for the price you then paid for it.

Not sure if these were implied in the original question: Nikon F2, the electronical F3, and any Leica rangefinder camera and the Rolleiflex medium format camera.
They may need a very occasional lubrication but that's it. I hav ebene using a 1950s Rolleiflex very often (though now I mainly shoot digital). It is still capabable of outstanding results.
Also a number of mechanical watches can be enjoyed for decades. Rolex of course. But at the lower end of the price spectrum automatic Seikos will also last a long time, or Omegas from before they were a "serious" brand will also last for decades.

The Amish would survive rather well, I expect. Add a few young surgeons and you're set up for survival.

True, but in Sg there is no indication that they do.

Indeed, street criminality is very low. Tokyo is a pleasure to walk around at night. There may be relatively dangerous areas that I am not aware of, but not at all on the level of certain american cities.

It was a figure of speech. I meant, it is very difficult to find a dangerous area in Singapore. The most seedy place is probably Geylang and it is still very safe. There are areas in for example Brussels and Paris (both are otherwise nice cities) where I prefer not to walk at night. Probably nothing would happen, but the feeling of being less safe is palpably there.

Your point being?

Look, I agree with the principle about democracy. However, living there I began to change my mind, perhaps democracy is not as good for the population as enlightened despotism like in Singapore. I originte from Belgium where so many issues and projects simply get stuck in endless politicall squabbles. Not so in Singapore which is run like an efficient company. You have to live there to appreciate it.

Again, if you are into drugs, then it is best to stay away. Everyone in Signapore, not just the government, prefers you being not in their country.
Honestly, what is bad about that? Drugs are linked to increased criminal activity. The city state successfully scared off the smugglers.Perhaps the USA should take an example in this matter instead.

Regarding "jailing homosexuals", you are plain wrong. There are a good number of lbgt people in the city. It is true, very unfortunately it is still somewhere in the laws that it is forbidden, but to my knowledge it is only referred to in case of rape, paedophile misdeeds and the like, making the related punishment heavier. The city is not persuciting the lbgt community.

And your statistics are ridiculous, if you do not indulge in obviously criminal activities you will not get executed.

What is so difficult about leading a normal, non-criminal lifestyle?