How do unions make shitty employees unfireable? From what I've seen, collective bargaining agreements usually mandate two things:

1. Documentation of 'just cause' for firing. Unlike standard at-will, you need a real reason to fire someone like poor performance.

2. You need to follow the specified disciplinary process.

This is just a formalized, bureaucratic version of the process that any legitimate termination for performance is going to follow anyway, so I'm not sure how it's a huge change.