>>That seemed to happen around 60ish people.

The moment your boss has a boss, its just plain easy to hide.

The most important thing to understand about big people structures is every thing is a 'cost center'. The expenses aggregate at your boss, its irrelevant who is consuming how much in a team. For example Boaty McBoatyFace could have negotiated a big bonus from his boss Scrooge McDuck. Scrooge could have 10 people reporting to him, but Boaty's bonus is largely an expense divided by 10 across Scrooge's team, and largely appears as expense per person to the Scrooge's boss.

More precisely its like

    SELECT SUM(person_expense)
    FROM expense_table
    GROUP BY manager_name;

Sure some one could fire a query and see it was not 9 people who ballooned Scrooge's expenses, but only one employee called Boaty. But almost always no one does that(Because people who deal with expenses interact through Dashboards, not SQL queries).

I learned this first hand from my ex-manager. Also most organizations are likely to fire queries along the lines.

    SELECT SUM(expense)
    FROM expense_table
    GROUP BY expense_category;

expense_category being things like lunch, project outing, education etc. Then companies decide to cut down on budgets related to that category. But that's on the common category alone.

Say an expense category was 'bonus', or 'stock grant'. Its very common in most orgs, that in a team, for 2 - 3 people to eat the whole team's budget, and yet be totally invisible. And better, make it look like the whole team finished the budget.

Same thing in the hedge fund space. When you start seeing people walking around who are basically like Creed from The Office and you start to wonder 'what does that guy actually do all day'. It's normally a good indicator that PnL is going to get rough.

But it also helps that the relationship between money in and money out is more explicit in finance. The feedback loop is more immediate.