[hellodevnull]

Same logic is used in free market arguments: Workers leaving jobs to go to other companies creates an incentive for employers to improve work environments.

In both scenarios the workplaces become better off, but what really happens in practice is less than ideal.

[imarg]

Yes but what happens if you are poor and living paycheck to paycheck? And what if there are not enough jobs? You have no choice but to stay in a job no matter how bad it is.

BI supposedly will give you a choice. You won't starve to death if you leave your job.

[ConfuciusSay02]

UBI is not an alternative or opposite to free labor markets. It simply provides a baseline level of income so that at the bottom end, the driving force behind an employee's decision to take a job or not is not driven by things like starvation.

[geon]

You can only leave a job for another if there actually is another one.

[mgkimsal]

Or... if the other job is literally no better... there's no positive benefit to be had, and possibly negative backlash.