The thing that annoys me is when people use stats like this to pretend the officials of football history have some kind of hidden agenda or that there is a mystical barrier stopping foreign managers, when really it is just the usual nonsense of tournaments being rare, federations being cautious, and the best jobs going to whoever is already trusted by the country, and then every cycle people start with the same talk and ignore how much the structure of the competition itself favours continuity, so no I am not buying any grand theories from this at all, just a quirky fact and nothing more