I don't get something so maybe somebody can explain. Afaik, France has nuclear reprocessing plant, basically they take used fuel, separate nonrecyclable parts a

I don't get something so maybe somebody can explain. Afaik, France has nuclear reprocessing plant, basically they take used fuel, separate nonrecyclable parts and get new fuel to be used again in their reactors. Why other countries don't send their used fuel to France for reprocessing? Is it too expensive? Too dangerous to transport? limited capacity of the plant? Or that the produced fuel can't be used in reactors from other countries? Also, why don't other countries build similar plants?