If one looks at it from economic-theory or game-theory perspective it sounds like a solution to many problems, nobody knows yet if that would work in practice though, especially on large scale.
As far as I know, open questions that remain are:
- Will we be able to afford it? Sort of back-of-the-napkin calculations can show, that if we introduced i.e UBI in Germany for everybody (80 mil) on a level of minimum wage (1473 E ?), it would eat their federal budget for Ministry of Health and Social Security and Ministry of Economics and Labour
- What would be the unintended consequences? (i.e on small scale uneployment rose by single digits, but we can't really tell what will happen on country scale)