It is very rare for someone that is fired to be "guilty of misconduct," unless you consider poor performance misconduct.

In Britain we have quite strong employment laws and a bit less of a ruthless corporate culture, so in many sectors it's fairly uncommon for people to be terminated for poor performance, so I suspect "misconduct" is a higher percentage of overall firings here.

Yeah for sure. Unfortunately in the US it’s not uncommon for companies to find “a pattern of behavior” or “less than stellar work” that is enough to justify not giving you your severance, but also not too severe that they can’t be blamed for never bringing it up and putting you on a PIP (performance improvement plan, not sure if that’s a term in other countries).