To be blunt, it doesn't matter if it actually happens or not. It's about risk management. It is absolutely the norm in most companies to remove an employee's access to company resources if the termination was not the employee's idea.
Other than general goodwill, there is no incentive to give an employee a heads-up that they are being laid off. And lots of downside if the employee happens to be disgruntled and do something evil. Goodwill does not show up on balance sheets. But theft and sabotage do.
"The value of a company’s name, brand reputation, loyal customer base, solid customer service, good employee relations, and proprietary technology represent aspects of goodwill. This value is why one company may pay a premium for another."
Other than general goodwill, there is no incentive to give an employee a heads-up that they are being laid off. And lots of downside if the employee happens to be disgruntled and do something evil. Goodwill does not show up on balance sheets. But theft and sabotage do.
I'm not saying I like it, but I understand it.