[pjlegato]

The fatal problem with any universal basic income scheme is that people will always vote for whatever politicians promise to augment their basic income, irrespective of any other factors, leading to ever higher strain on the economy and eventually bankrupting the country.

[lukeschlather]

Basic income is actually pretty rare, even among democracies. So it would seem you are empirically wrong. Not only will people not vote to augment basic income, they won't even vote for a modest basic income.

[pjlegato]

Few politicians have seriously proposed it so far. If and when they do, the votes will follow (a testable prediction.)

This process has indeed happened already. It was a large part of the downfall of ancient Rome. Glossing over the many details, when slaves were doing most of the work, people supported those politicians who offered them ever increasing grain doles, until the state could no longer afford them and collapsed.

Socialism in general is a variant of the basic income scheme, and hugely popular: a state guarantee of a certain basic income and level of material security, no matter what happens to you in life. It has done well in elections for a long time and remains popular today, as well as driving various popular Communist revolutions on a non-democratic basis.