Money will eventually circulate everywhere, but it's a matter of efficiency. This is an immense simplification, but to illustrate the intuition, consider 2 options:

1. Apple spends $10 million dollars to build a factory in a developing country. This creates 2,000 jobs over a couple years. These people can finally afford to see a doctor and heat up their homes during the winter.

2. Apple gets taxed $10 million that funds 1000 people's UBI. Their lives are somewhat less stressful. There is a higher demand for Iphones, so Apple can charge a bit more money for them. After a decade, they are able to open an additional factory. However, within that decade, 100 people in that developing country died of a disease that would be easily cured with medicine had they had they been able to work at the factory 10 years ago.

The money to pay for UBI doesn't come from a mattress, either. It comes out of money that was invested.

Trickle up economics?

Since trickling down doesn’t work, if UBI doesn’t work either, we need a new proposal.