> and lots of people decide to go away from their existing companies and work for the shitty companies, then you have to at least entertain the notion that you were wrong about what makes a job shitty

There's a lot of churn in the job market, so people go in and out of work frequently. They may spend a few weeks or months claiming unemployment benefits. In the UK that would be Universal Credit, and some people claiming UC were forced into working zero hour contracts for companies like Uber by the DWP.

For many people it's not a choice.