If you look at the case of Japan, they've just signed a free trade agreement with the EU, so at the same time barriers are going down there, barriers are going

If you look at the case of Japan, they've just signed a free trade agreement with the EU, so at the same time barriers are going down there, barriers are going up in the UK. Given that the Japanese car companies only came to the UK to access the single market, why would they stay now that Japan is 'closer'?