There's no "guarantee" but there's an increased probability, coupled with a good employee's ability to move to an employer that values someone like them.
In the union mindset, there's no chance to do better - it's all been traded away for the chance to do "no worse than" which by definition benefits the less good/productive and hurts the best people.
In the union mindset, there's no chance to do better - it's all been traded away for the chance to do "no worse than" which by definition benefits the less good/productive and hurts the best people.