Because for all the faults that unions can have (and they certainly can), their decline correlates to the rise in short-term shareholder interest trumping all other efforts, which is unhealthy for businesses and society.
(h/t +Wendy Cockcroft)
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I’ve Always Hated The Idea Of Labor Unions, But It May Be Time To Reconsider
The new obsession with “earnings maximization” is wrecking the economy.
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I have said often enough that a company must serve its investors (shareholders), members (employees), or outsiders (customers). The neglecting of the latter two for the former is not good in the long run for anyone.
Neglecting any one of them is problematic; neglecting any two for the sake of the third will lead to bankruptcy, sooner or later.