BASEL, Switzerland — With 1,155 parts in the movement and 40 functions, including 23 complications and 17 “technical devices,” the Audemars Piguet Code 11.59 Ultra-Complication Universelle RD#4 has been hailed as one of the most complex watches ever made.

But why? Who needs 40 functions on their wrist?

“That is a good question,” the master watchmaker Giulio Papi, technical director of Audemars Piguet Le Locle, said with a laugh during a recent telephone interview. “When you spend 1.5 million Swiss Francs, maybe it is for other reasons than for practical reasons. You are probably a connoisseur collector, an amateur of mechanical solutions and fan of Audemars Piguet.

“You don’t need this watch to survive in the forest,” he said, alluding to the fact that mechanical horological functions are no longer necessary for everyday life.

In 1986, Mr. Papi co-founded with Dominique Renaud the workshop Renaud et Papi, which in 1992 established its own manufacture to create complicated timepieces for brands like Richard Mille and Audemars Piguet. The factory has been wholly owned by Audemars Piguet since 2018.

To create such watches, he said, “is to show the know-how of a brand. And from the collector point of view: They love mechanical things! I don’t think there is one reason. There are a mix of different reasons.

“For psychological reasons: It’s a push of research and development in an elite for the elite,” he said. “Such a watch is not a product for everybody.”

One of Mr. Papi’s quests is to make extremely complex watches as innovative, user-friendly and ergonomic as possible. The RD#4 is considered surprisingly wearable, with a diameter of 42 millimeters and a height of 15.6 millimeters.

Claude Sfeir, a jeweler and gemologist based in the United Arab Emirates, is familiar with how fragile super-complicated watches used to be. He is also a well-known watch collector and a longtime Grand Prix d’Horlogerie de Genève jury member.

“Nobody, or maybe 5 percent of collectors, read the manual,” he said by phone from the back seat of a car meandering through traffic in Dubai. “And that’s why you find a lot of complex watches come back to the workshop for repairs — they don’t know how to use them.”

Mr. Sfeir compared an extremely complex watch that has a multitude of functions with high-end cars: “Collectors like the look of the watch, but it is like the options in a Ferrari. You have many options, but you don’t use most of them.

“You may understand time — the chronograph, yes; a split second, yes; the perpetual calendar, yes. But beyond, with tourbillon, minute repeaters, grandmaster chime, etc., nobody understands — you must be a watchmaker of high level to really understand how they work.”

His own knowledge about watches has come a long way from when he started in the Dubai souk in 1980, dealing with timepieces only for the inherent value of their gold and throwing away the movements.

Among his own most prized watches is the only known Sky Moon Tourbillon in titanium, which has the unique reference number 5001T; when released in 2000, it was Patek Philippe’s most complicated wristwatch.

Its escapement and complications include a tourbillon, a perpetual calendar, a retrograde date, a sky chart, moon phases, an orbit display and minute-repeating on cathedral gongs.

“I also have some grande sonnerie watches from A.P., F.P. Journe and [Philippe] Dufour,” Mr. Sfeir said.

“My fascination about super-complex watches is that they are so difficult to produce,” he said. “You have this very small case, and inside you can have 800 or even 1,300 components — that’s what makes this level of watchmaking so, so incredible.”

Stefano Macaluso, a watch designer and a former product and development manager of Girard-Perregaux, has experienced the whole spectrum of collectors’ knowledge. Sometimes they are more knowledgeable than he is, and sometimes, well, a little less knowledgeable.

“Around 2005, we sold a unique minute-repeater that cost 500,000 francs [$552,000] to a country in Central Asia,” he recalled by phone, referring to a complication that plays musical notes that tell the time through complex miniature hammers and gongs when a lever on the side of the case is pushed. “A year or so later, I met the collector who bought it, and he said, ‘Wow, I really love this watch! And the watch also makes music — did you know that?’

“That was typical of the times — many were enthusiastic about Swiss complications as a luxury item, as a paramount of technology, but they had little knowledge. Today, collectors are more developed, they have more expertise, they are less naïve.”

According to the watch industry consultant Gianfranco Ritschel, things like that still happen, “especially with brands that are specialized in the phenomenon where a high price makes a product more requested.”

Mr. Ritschel works with the Fondation de la Haute Horlogerie, a nonprofit foundation set up in 2005, where he trains sales staff around the world. He said it was rare to find a collector of ultra-technical watches who was not familiar with how complications worked.

“Today, when you buy a high-end complication, it is not just about purchasing an object, but it is an experience that can start in a boutique,” he said.

“And part of this experience is to discover and to know the piece — the product becomes a symbol for this education,” he said. “I know a lot of Chinese clients who are so much more expert than clients here in Europe. They come here to Switzerland to meet watchmakers and learn more. These kinds of discovery and knowledge trips are today often part of purchasing this kind of luxury.”

At Girard-Perregaux in 2017, Mr. Macaluso designed the highly complex Minute Repeater Tri-Axial Tourbillon. From a watchmaker’s or a designer’s point of view, he said, creating extremely technical watches goes beyond mastering the technical challenges because they are also potentially more profitable.

“Since you take a higher risk in the design and development, it makes sense that the margins are higher for such watches,” he said.

Mr. Macaluso, a car collector, also is partial to an automotive analogy, comparing the urge to own a super-complex watch to one for a car with a roaring 12-cylinder engine: “You don’t need 12 cylinders to go fast, and you don’t need a minute repeater to tell the time. But you take pleasure in knowing that it is a sophisticated, mechanical top achievement.”

Aurélie Streit, vice president of the F.H.H., said she saw two trends in clients for ultra-complicated watches: “The ultra-geek and the show-off peacock.

“The peacock wants to show how powerful they are. They want the most complicated watches, the biggest yachts, the fastest cars. But the ultra-geeky customers are truly fascinated about mechanical things, fascinated about what human beings can do with mechanics. And they know the value.”

It could be that they view the ultra-technical, most complicated watch as a good investment because it is different, she said, adding that beauty and usefulness have pushed the limits of horology in the past.

Uniqueness can also add to the value.

“I like to open it to see so many parts doing so many things,” said the French businessman and collector Patrick Getreide about his 20-complication Patek Philippe Grandmaster Chime Ref. 6300GR-001, now the most complicated wristwatch Patek has made. “But I am not the one to stay one hour to look at it.”

Its 20 different complications, divided on two dial faces, include grande and petite sonnerie, a minute-repeater and an instantaneous perpetual calendar.

“I am not technical. I read what they say about the watch, and I recognize that it is fantastic and what it can do — but I am not a watchmaker — I bought all my watches with my feeling and my passion, and with help from experts,” said Mr. Getreide, renowned for his approximately 600-piece OAK watch collection. (OAK stands for “one of a kind,” and many of his pieces were shown at a Design Museum exhibition in London in 2022.)

Most of the collection consists of rare and understated pieces, both vintage and modern. But now, after acquiring the Grandmaster Chime this year, Mr. Getreide has entered much more complicated territory. “I will wear it if I want to show off and make some people jealous, people I don’t like,” he said jokingly during a video call, adding that other passions, including for his dogs, soccer games and his family, are more important to him than watches.

“For my watch collection, I rely on the experts to explain to me the particularity, but most of the time it goes into one ear and out of the other,” he said. “But I just know when I want to have a watch.”

To the Swiss psychoanalyst and historian of ideas Dr. Daniel Strassberg, the author of the book “Spektakuläre Maschinen” (“Spectacular Machines,” published in 2022), watches and clocks go beyond all that.

“The mechanical clock was one of the most important machines ever designed; it shaped a whole world of thinking,” he said during an interview at his Zurich practice. “There is something special with a watch, which is different from a car or a jewel or something.

“The watch has a very old mythological, or even theological, meaning, as the clocks made us independent from God and nature, since the clock produces the time it measures, independent of the time that God created. Since the 17th century, we have the feeling that we are the masters of nature, and I think that there is no stronger symbol for that than the watch.”