Handset UIs don't travel
Japanese don't buy European handsets: "Nokia denied that there was a sales problem but admitted that there was "user confusion" over Nokia's keyboard buttons since Nokia insists on using a different convention to other handsets in the Japanese market."
And hmm, look at the poorest handsets that we get over here: those with UIs from Japanese manufacturers (yes NEC, I'm looking at you) which just haven't adapted to the UK. I'm increasingly coming round to the view that UIs are much more culturally dependent than I'd realised, or that there is some sort of Asia/Europe/USA divide, which seems ridiculous to me intellectually but seems to be the case: American handset UI is awful but tolerated over there, European UI seems to be OK and transfer well across European territories, and Chinese/Japanese is terrifying to a poor old European (and vice versa).