Suppose management is messing things up. Chances are good they’re deluding themselves about the consequences of their actions.
If team members trickle away one by one, each departure is easy to rationalize, and the deluded behavior can continue.
A spinoff can be harder to cope with, because more people leave at once, but it probably won’t take the entire team. There will still be the more timid, those less good, those whose skills don’t match the startup. That allows management’s deluded behavior to continue, and rationalization is even easier — “they saw an opportunity and took it. It has nothing to do with *us*”.
In both of these cases, those left behind continue to suffer, probably even more.
But if an entire team walks, that’s much more like an addict’s “hitting bottom”. The consequences are going to be huge because any new team would have to learn the system from scratch. (Though I suppose management could delude themselves into thinking they have the project documentation to make that tractable.) And the departure of any series of employees [or, in the case of an addict, friends] is easy to rationalize: “he’s just a malcontent [no fun any more since he got married]”. But when *everyone* rejects you at once…
In the normal case, there’s a power imbalance. To a reasonable approximation, management and the employee start by making what each considers a fair trade. (The employer gives up money; the employee, time and other opportunities.) But each employee [usually] needs her job more than management needs each employee because all of her revenue comes from one source, but each employee provides only a fraction of the company’s revenue. That means that what was originally a fair trade can most easily become unbalanced in management’s favor.
If an entire team can reasonably threaten to quit, that helps restore the power balance.
Note: I’m not claiming that only employers get dysfunctional. And I’m leaving aside ways in which employees have more power. For example, each employee [usually] has more information about how well she’s working than management does, so she can do less work than the deal called for without getting caught. (Think of Wally in “Dilbert”.)