Having said that, in finance (I used to work at a proprietary trading firm in an at-will state), it’s extremely common for firings to be immediate, e.g., arrive at work, boss calls you to office, get fired, badge taken and you’re walked out and your desk belongings are mailed to you later. More often, you’re walked to your desk to pick up your things instead of having them mailed out, but both happen. But even more often, people are “incentivized” through bad reviews and bad bonuses to quit in advance of a firing.
When I quit, they didn’t want me to leave, and I negotiated a couple weeks of notice to hand over my responsibilities and knowledge, and to maintain some relationships.
I had a non-compete in my original contract, so I would have to negotiate with the original firm as to whether they would enforce it. If so, I would receive gardening leave pay in order to delay my employment at a competing firm. That could be for as much as 2 years, and they would pay my base salary at the original firm in order for me to not start at the competition. This gardening leave is totally different than a severance package though.
In Britain it's called gardening leave, and it's common in finance and other jobs with tight security. You are paid, but you stay and home and do some gardening. (Or, more likely, look for a new job.)
I understand it happens, but it seems _way_ too common (reading the comments here) compared to what is actually necessary.
Edit with example: https://www.arbeidstilsynet.no/en/working-conditions/dismiss...
> An employee may usually remain in the post as long as negotiations or legal proceedings are in progress, provided the courts have not decided otherwise.
> [...]
> The employer may summarily dismiss an employee if he or she is guilty of a gross breach of duty or other serious breach of the contract of employment. The employee has no right to remain in his post while the matter is being considered, unless the court has decided otherwise.