Of course there are different environments. If you work in the public sector you won't be fired unless you break the law. If you work somewhere with a lot of investor money coming in, then your employment is not dependent on your productivity. As long as the money keeps coming in, you're safe. Once it stops, everybody is out, even the hardest workers.

And there's even good companies, where they will give a bad employee a chance to become better.

But in more everyday workplaces you first don't get hired unless you're productive, and you secondly get fired if you're not productive. When/if the boss comes around to threaten about working harder, it's almost always a scam, because if there really was any issue, you'd been fired already. This becomes less and less of an issue the better paid a job is, because at the higher levels people know well if they're good or not.