A Swiss watch is a quality standard in the world of watches.
They are produced by prominent brands. They also have a long history, their own unique developments and individual "handwriting". It is impossible to make an unambiguous rate of the Swiss watches brands, because their advantages are determined by a whole range of criteria.
This list will mention aspects of the watch or its construction that are often function agnostic. More over, these items are overall things to look for.
There is no "perfect" watch, so just make sure the watches you are looking for satisfy as many of the items below as possible.
An automatic movement rather than quartz
The traditional – and most expensive movement – is a mechanical which doesn’t use batteries.
Most mechanical watches in the luxury watch market are "automatic" which means they don’t need winding up thanks to a clever spring (as opposed to a "manual" mechanical watch which needs winding up regularly).
Some of the best watch brands make their own movements "in-house" which is seen as a badge of honour and offer and an extra level of exclusivity.
A "synthetic sapphire" crystal
A watch crystal is the transparent cover over the face of the watch. And you’ll find the best and most expensive watches have a crystal made from "synthetic sapphire", which is a very scratch resistant material. A cheaper option is "mineral glass" but go for synthetic sapphire crystal if you can afford it as it is more likely to survive a massive whack.
A "chronometer" rating
This is something that not all luxury watches have by any means, but can add value and reliability to your watch.
If it says something like "chronometre certifie" on the dial then it has gone through the Contrôle Officiel Suisse des Chronomètres (COSC) process, which tests the watch in different temperatures and conditions over several days.
A case and strap made of solid metal (or leather)
Cheap watches use hollow stainless steel in the straps, whilst lower end luxury watches use solid stainless steel. You should be able to tell from the weight.
The more expensive luxury watches will be made from precious metals such as gold (18 carat) or platinum, which is generally pricier than gold.
Of course, you do also get high end luxury watches with leather straps (such as this Hublot watch). These tend to be lighter, which is some people’s preference.
At the very top of the watch market, you’ll find that timepieces are blinged up with diamonds and other gemstones to add value.
Keep in mind that prices in the diamond market fluctuate, so it's hard to know how much of a good deal you are getting. For example, several smaller diamonds are worth much less than one large diamond of an equivalent weight.
And then of course, each diamond has its own grading based on its cut, clarity and colour. Generally, famous watch companies with well-established jewelry making arms are going to have the best types of stones utilized in their high-end luxury timepieces.
Most watch companies in the world do not make their own movements. They source movements from various movement suppliers.
The most well-known European watch movement maker is ETA, and is part of the large Swatch Group. Some companies purchase movements and use them as is, and other times, they modify or add to movements (modules) making them more unique and complex.
This also involves various types of decoration that a watch maker might include on a movement. The best watch makers design and construct their own movements in-house – even if they don’t make other components of the watches.
Complications are the various dials and other things that a watch does beyond telling the time.
Others, such as Breitling often include a few of the more common complications, such as the date and a chronograph.
Other common complications in high end watches are perpetual calendars, rattrapante chronographs, sonneries, fusee and chains, moon phases, and multiple time zones along with world timers.
Be cognizant of what complications the watch you are looking at has.
Sourse: Best Watches Guide