Serial founder Bridger Pennington panned his camera around an office full of people still at their desks on a Friday evening to prove his point that in-office working is more productive.

“I get a lot of hate, but I’m a big believer for working in an office in person,” Pennington posted to his Threads account, where it’s racking up thousands of reactions. “You can look at the time, it is five exactly on the dock, and you can see everyone’s still working.”

The Utah-based co-founder of the startups Fund Launch and Ugly Unicorn explained that, despite offering workers incentives to work in the office—including free dinners for anyone who stays past 7 p.m.—he still faces backlash for not letting staff work remotely.

“You try that with your startup, go ahead. Good luck,” he bluntly responded to anyone pushing back on him. 

“I’ll bet your bottom dollar, Susan or Joe, whoever, on a Tuesday afternoon that’s working remote, 30% of the time they’re getting groceries, they’re running their dog to the vet, they got a kids dance recital—they’re not working, and you’re paying them full time.”

The internet fired back—and some of them do run their own companies

Pennington captioned his video, telling people to run their own company if they weren’t happy with his stance on in-office work. So naturally, founders came to his comment section to let him know they already do—and that their remote-first firms are thriving.

“Seeing this while my team helps me run a successful company from their beds or the beach, in different continents,” one user—who says she runs her own company with an entirely remote, women-only team—commented.

“No clocking in. No permission slips… I give them paid leave for periods because day two under fluorescent lighting is not it,” she said. “Daycares for their kids are covered too.”

“I do in fact run my own company. My employees are all remote and incredibly hardworking,” another user added.

Others pointed to Fund Launches’ 3.1-star Glassdoor rating as evidence that not everyone who works for the company is as happy as Pennington is with its in-office policy and company culture.

Meanwhile, remote workers took to the comments to argue how much more productive they are from home and that Pennington’s take has “micromanager written all over” it.

But Pennington pushed back, telling Fortune that in-office working is beneficial for both workers and company culture.

“Especially post-COVID, many young people want to work on something compelling, with people who work hard and build something fun together,” he said.

“That’s the culture we’ve built at Fund Launch, and it’s a cascading effect. It’s energizing, fun, and exciting to work with great people on really hard problems, especially when you know you have upside in the company you’re building.”

Workers and their bosses have very different definitions of productivity

As Pennington points out, he believes workers are less productive at home, not because of their output levels, but because he sees them having time to run errands. Whether or not his 30% figure holds up, he’s put his finger on a tension that isn’t going away: workers and employers genuinely cannot agree on what a productive day actually looks like.

Research has shown that only 25% of workers measure their productivity in any formal sense—meaning most people rely on something far more subjective, like ticking off a to-do list or simply feeling done for the day.

A key way many workers say they measure productivity is by being able to get their stuff done “without roadbacks”—something which the office is full of: The impromptu desk chats, the colleague who needs five minutes that turns into forty-five, the back-to-back meetings that could have been an email.

And yet Pennington describes being able to quickly tap a colleague on the shoulder as one of the biggest draws to working in an office.

“In person is such an advantage,” he said, while pointing to two young hires who are sitting in an open-plan office where you can overhear every conversation. “These guys all get to learn and be like around those people,” he added. “When you work in person, you can walk around and talk to people and get stuff done and just get things moving.”

Ironically, those same spontaneous interactions are precisely what remote workers cite as their biggest productivity drain when they’re in an office. 

Because while visibility may feel more productive for a manager—being able to see who’s at their desk, loop someone in on the spot, get a quick update in passing—for the individual contributor doing the actual work, those micro-interruptions compound, leaving them with less time to do their actual job.

It’s why workers and their employers may never see eye to eye on what constitutes a day well spent at work.  

Remote employees may argue they’re more productive because they can do their jobs two hours faster, sans distractions, than if they were in an office—leaving them extra time for life admin. To them, that’s proof of efficiency. But to their boss, it may look like two hours they weren’t working.