But there’s one titan of industry bucking that trend: JPMorgan Chase CEO Jamie Dimon. In his letter to shareholders, published Monday, the investment bank’s longtime chief executive praised the agility and ownership of small teams in military terms. “The teams needed to tackle [specific problems] should be small and authorized with the decision-making ability to move and act like Navy SEALs or the Army’s Delta Force,” he wrote. “This is trench warfare; it’s about fighting for every inch, moving quickly, and getting things done.”

There’s some basis for the comparison with special forces operations: The SEALs are known to work in squads of eight or fewer, for example. And in the business world, organizing workers into smaller teams can ensure that everyone has a stake in the outcome, Dimon argued. 

In a team with too many members, accountability is spread too thin, he wrote: “Very often when a management team wants to accomplish something new … everyone on the team says, ‘We’ll get it done,’ meaning they will add it to the long list of tasks already on their plate. But when efforts are 1% of a lot of people’s jobs, it will never get done.” 

Smaller teams, with shorter “to-do” lists, are incentivized to give their full focus to any given task, he explained: “You need a team 100% dedicated to the mission—and everyone else supports them.”

In championing smaller teams, Dimon is at odds with the ultra-flat management model being adopted by firms like Meta, where CEO Mark Zuckerberg is expecting workers to do more with less in the AI era. The tech giant has laid off hundreds of workers this year and implemented worker-to-manager ratios of 50-to-1 in at least one department—a lopsided organizational structure that’s far beyond even the outer limit of the so-called span‑of‑control scale (which measures how flat or hierarchical a structure is by how many direct reports each manager has).

Eliminating layers of management is intended to speed up decisions and innovation by cutting hierarchy and bringing leaders closer to frontline employees and customers, thereby boosting engagement and ownership. But in such arrangements, junior staff can get overlooked, employees can feel directionless, and managers can burn out—or, as Dimon points out, accountability for getting things done can be diluted.

Despite those risks, U.S. companies are continuing to “flatten,” according to Gallup. The average manager’s span of control grew from 10.9 direct reports in 2024 to 12.1 in 2025, meaning average team sizes are now nearly 50% larger than when Gallup first began tracking them in 2013.

Flat structures often don’t last long, as employees gravitate toward more managerial interaction. “What happens in most organizations is eventually either a formal or an informal structure appears sort of underneath direct reports,” André Spicer, executive dean of Bayes Business School in London and a professor of organizational behavior, previously told Fortune. 

The general consensus among management experts is that the ideal team size is seven, give or take a few. Former Amazon CEO Jeff Bezos famously captured this idea by introducing the two-pizza rule in the company’s early days; if two pizzas can’t feed a team, the team is too big. 

That illustration seems almost quaint now, but the central concept still holds. Dimon has landed on roughly the same team size, only he made his point—perhaps fittingly in a time of war—with a military metaphor.