This is an important point, especially because the first country that implements UBI will be the most attractive country to immigrate to for people who have no

This is an important point, especially because the first country that implements UBI will be the most attractive country to immigrate to for people who have no value to employers. Many potential immigrants who want to work hard will choose to go to other countries, so the country with UBI will miss out on their productivity and their tax dollars. That would certainly put a burden on the UBI system.