[paxys]

From my experience at several (large, well-paying) software companies, I feel like this is already the case.

Employees who leave voluntarily will usually give as much notice as they can. There is no fixed guidance or expectation, but just good form to tell at least your manager as soon as you have made a decision. It isn't uncommon for people to publicly announce their departure 6-8 weeks in advance.

For people who are fired for bad performance, there is usually a PIP or other probationary period which would count as notice.

For layoffs, there will be severance (2-3 months is common).

The only time I have seen abrupt departures is for entirely unavoidable reasons – theft, sexual harassment, family issues, visas.

[d3nj4l]

Yeah, it's pretty rare to get a PIP that isn't basically a "You're being fired in 3/6 months" notice. It's unfortunate because getting PIP'd is pretty stressful, so it hurts your ability to find another job as well.