And even after following such detailed guidelines, you can still get it wrong: according to the men's style blog The Art of Manliness, when attending a black-tie affair, "the implication that you would check the time is considered rude to the hosts." In other words, when worn with a black-tie ensemble, a watch—even one that matches one's cuff links—is inappropriate.
And yet the typical black-tie soiree is a come-as-you-are shindig compared to a day at the races in the Royal Enclosure at Ascot, where:
Ladies are kindly reminded that...
Dresses and skirts should be of modest length defined as falling just above the knee or longer.
Dresses and tops should have straps of one inch or greater.
Trouser suits are welcome. They should be of full length and of matching material and colour.
Hats should be worn; however a headpiece which has a solid base of 4 inches (10cm) or more in diameter is acceptable as an alternative to a hat....
Strapless, of the shoulder, halter neck and spaghetti straps are not permitted.
Midrifs must be covered.
Fascinators are not permitted; neither are headpieces which do not have a solid base covering a sufficient area of the head (4 inches/10cm).
As for men, even an immaculately correct dinner suit ensemble, watch left safely behind at home, would be out of place at Ascot, where:
[I]t is a requirement to wear either black or grey morning dress which must include:
A waistcoat and tie (no cravats)
A black or grey top hat
A gentleman may remove his top hat within a restaurant, a private box, a private club or that facility's terrace, balcony or garden. Hats may also be removed within any enclosed external seating area within the Royal Enclosure Garden.
The customisation of top hats (with, for example, coloured ribbons or bands) is not permitted in the Royal Enclosure.
Such nitpicking isn't limited to unusually fastidious businesses and old-fashioned festivities. In 2018, I asked Kate Lanphear, creative director of Marie Claire magazine and a self-described "punk-rock girl," about today's dress codes. She pointed out that even oppositional subcultures that pride themselves on breaking all of the rules still "follow a code.... The patches you put on a denim jacket or the pins, the band T-shirt you're wearing is still a code to other people to identify with... [they're saying] I'm part of this tribe... [they're] following the code of the rule breakers." In other words, those rule breakers replace the old rules with new rules—often as uncompromising as those they just broke. Here, I am reminded of the Pinnacle Peak Steakhouse in Southern California, known for its large portions and rustic atmosphere, where employees wielding scissors cut off the neckties of unsuspecting businessmen: the work-a-day rule requiring neckties is replaced by an after-hours rule forbidding them. Similarly, free-spirited college students who blanch at the idea of a dress code imposed by university administrators seem happy to conform to intricate unwritten rules about attire: campus social cliques are readily identified by their shared style of dress, and the fashions of just a few years ago are as completely absent as if they had been prohibited by law. Their professors, for their part, advertise their disdain for surface appearances with a deshabillement that has become a kind of academic credential: the naïve assistant professor who wears a Dolce & Gabbana dress to a faculty meeting may need years to recover an aura of scholarly gravitas. Even the Silicon Valley style of casual wear has become a kind of dress code: if a sweatshirt and flip-flops demonstrate a single-minded focus on innovation, a suit and tie betray an outmoded concern with appearances and status. Accordingly, one Northern California investor advised to "never invest in a tech CEO that wears a suit...." These unwritten dress codes can be as powerful as rules inscribed in law and enforced by police.