Comment by conrs

The trouble is this calculus is being done at the local level despite the mantle of responsibility of management; the manager decides it is not worth their personal effort to lose a low performer, because they will generate more work for themselves. Meanwhile, the company suffers the net negative impact of such a decision - arguably even worse for the manager's career.

That's the main challenge I have coaching management folks - now you have the option of doing work, and often you'll be tempted to take the path of least resistance, but that'll usually lead you astray.

Edited to add - sorry I missed your net negative comment - to touch on that, as it's another thing I see often.. Giving up on the org's ability to satisfy your needs is another toxic pattern for management - it is a lose/lose essentially. Management is often in a position of needing to push for the things it needs and advocate for the people relying on them.