Joseph Stoker was sitting on the couch watching Netflix's "Big Mistakes" when his partner asked him about one she thought was an obvious blunder: What would he think if a candidate walked into a job interview with an iced coffee?

Stoker, a 40-year-old lawyer in London who works in-house at a tech firm, said he didn't think the drink would matter. It isn't evidence of a candidate's competence or capabilities.

Alicia Fairclough was shaken.

"The iced coffee would really bother me," said the 42-year-old founder of EA How To, a global community for executive assistants. "It just reads as too casual."

The couple spent the next hour hashing it out.

A simple question about chilled caffeine has sparked heated debates on couches and online about workplace decorum, highlighting shifting expectations of professionalism. Proponents say it's a way to show their personality-and after all, it's just a drink. For iced-coffee critics, the problem is what the beverage signals: casualness, poor preparation and bad time management.

Recruiters, job seekers and career coaches all have weighed in on the potential indignities of an iced beverage.

"It's...sipping, and swirling, and the noise, and the wet hand, and then also you think it drips," Caitlin Wehniainen, a Miami-based recruiter for Fortune-500 companies, said in an interview. "You're dripping down the initial lobby, then you're going up the elevator, you're dripping through the reception area of this office. There's just a lot going on, and why?"

The online fracas began brewing last week after Wehniainen posted a TikTok describing some of her Gen Z candidates walking into job interviews with iced coffee.

The divide mostly falls along generational lines. Younger candidates tend to see an iced coffee as harmless. Gen X and baby boomers see it as a breach of traditional corporate etiquette.

"It sets the tone, whether it's iced coffee or hot coffee, for more of a relaxed vibe," said longtime recruiter Peter Bennett, 66.

"If you can't go without a coffee drink for an hour, there's a problem," the Culver City, Calif., recruiter continued. "You can bring it in your car, take the final sip, leave it in the car."

His son, a 30-year-old content creator and partner at production company Kursza, was surprised by his dad's reaction. "I could care less if someone brings an iced coffee to an interview as long as they can execute the job," said Daniel Bennett, who's based in Venice, Calif.

For Zoë Hartsfield, the whole discussion is archaic and weird. "They could be the next Steve Jobs that you just passed up on, and you were too fixated on the fact that they had a beverage?" said the 30-year-old founder of brand agency the little ghost who lives in Denver.

Some career experts note that younger workers, who graduated into virtual interviews, may have had fewer opportunities to learn the choreography of a traditional interview.

Wehniainen speculated that a difficult job market may have left candidates desensitized to interview rituals and discouraged about their chances.

Candidates may be thinking, "How much should I really prepare for this if I don't even think I have a chance at getting it?" said Wehniainen, who loves an iced coffee herself but wants to help job seekers avoid missteps and land offers.

Employers should give candidates clear expectations, said Megan Slabinski, district president at recruitment agency Robert Half.

"They need to set people up for success and recognize that it has been truly a full generation of workers that have not experienced an in-person interview," the Seattle-based professional said.

And hiring managers might need to rethink their own ideas. An iced coffee shouldn't be grounds for rejecting a candidate. "Just bringing a drink to an interview doesn't mean that they are not good at the job," said Alina Nguyen, a San Francisco-based recruiter who's worked at Meta and Google.

Ultimately, experts say, it's about reading the room. For instance, an iced coffee might win points at a company in the caffeine business.

"We're more so looking for people with the right skills," said Kelly McCulloch, chief people officer for Inspire Brands, which manages Dunkin'. "It's not about beverages. We're going to offer them a beverage anyway."

Timing matters, too. "If it's 7 in the morning, then why aren't you bringing your coffee?" quipped Alisa Cohn, an executive coach and author in New York City.

If a candidate can't bear to leave their coffee at home, at least bring the heat, advised Cohn.

"Coffee is a little more formal than iced coffee," she said. "Coffee is dressed up in a jacket, right? Iced coffee's like a bathing suit."

Brandon Cho, the 34-year-old head of talent and culture at creative-communications agency Praytell, is currently in the middle of hiring. He's looking for curiosity and strategy, and wants people to come as they are.

Bring whatever you want, he said. He'll be bringing an iced vanilla latte with almond milk-maybe two.

But he reserves the right to judge you for your choices. "You bring a piping hot cup of coffee at 100-degree summer weather, I might judge you a little bit," said Cho, who's based in Los Angeles. "But I'm not going to be like 'Oh my gosh, you're so unprofessional.'"