If they don't, they simply are axed. I've seen it, and it is insult on top of injury. And the funny part is that the replacement employees are usually crap, even after the training. However, when the company's IT department falls apart and the stockholders come looking for those responsible, those responsible have taken their kickbacks and moved on, leaving their former company in smoking ruins, just like a 3rd world country...
Any replacement I train will finish by hating the company more than me. Poison the well when management is poisonous.
It’s an awful business plan but then “awful” was the word of the day in American business for a couple of generations.