If a employee is bad enough, then they are let go.
If they aren't let go, then they really must not be as bad as you say... otherwise why would the company keep them.
I'm talking about performance issues. It takes 5 forevers to get rid of them because it generally, though not always, has to be the same deficiency that persists.
First you have to OLCC them a few times. Then you have to give them documented verbal counselings. Yes, counselings - plural. After that you have to issue warning letters/performance reminders and it is preferred that there be at least a month in between each. Then he gets a decision day. Then he comes back and has to have ample opportunity to get up to speed with his personal performance plan. When it's clear that he hasn't, he gets his last letter/reminder and probably terminated.
If he GFTs it, there is a good chance that he gets it overturned with the instructions that his manager find a route or some other position that is more suited to his skill set.
Acceptable conduct issues are a different matter.