These sort of experiments do have to be made in these Scandinavian countries and perhaps a few others, maybe Japan. If you tried this in Latin America, well I'll tell you an anecdote, I actually don't know if it is true, an Argentinian engineer went to Stockholm and he went to the metro where he found several gates each with a place to pay passage and also a guard, but he was amazed to see a gate that had no guard and was completely opened so he asked a girl about this, she told him it was for people who for some reason couldn't pay their fare. The Argentinian asked her if they didn't fear people abusing the system and using this gate while having the money to pay, she just asked him "Why would someone do that?" The Argentinian knew that in all of Latin America that free gate would have a queue as long as the amount of people who wanted to board the train.
So you see for this universal income to work first you have to try it with people who have the right attitude towards it and don't see it as a freebie but as an opportunity to improve their lives.